IMEI number blacklisted by another company as "revenge"?

Question

This may be a bit of an oddball question, but hoping someone that knows of these matters can answer.
I have a subsidized/locked iPhone 5s via AT&T in the USA, and I'm on a 2-year contract with them. I recently (and still am) visited another country, and wanted to use my iPhone5s with a local (out of USA) phone number and SIM card. I came across a site (officialiphoneunlock.co.uk) that promised to unlock my phone. I believe my intentions were good... I just wanted to temporarily use a local number for my family to call me on while I was out of country. I still intend (and still am) to stay subscribed/paying for my 2-year contract. I feel that it is thus within my "rights" to use the iPhone with another SIM card if I want, but I suppose that's another debate.
The website  (officialiphoneunlock.co.uk) clearly advertised a price of 20 British pounds for an unlock for those of us on AT&T in the USA. As I proceeded, they did mention you'd have to do a "pre-order" and that any extra costs later (if any) would have the pre-order amount subtracted from them. But.. the advertised price for AT&T USA was the same as the pre-order deposit (others such as T-Mobile were more), so I went ahead and did it... It did seem kind of fishy. It also involved me giving them my IMEI number, which I did.
A few days later they sent me an email saying it'll be an additional 150 British pounds to complete the unlock. I engaged their support, saying the advertised price was 20 pounds... they never really directly responded to that... We went back and forth to no avail... finally I told them I was going to have my credit-card company do a "chargeback". Which I did, about one week ago. Today, the unlock-company wrote me an email about that, saying they will:
1) File a claim in county court for the cost of the service, plus additional court fees (which in GBP are expensive).
2) Blacklist my IMEI number within 48 hours - They say they will make it so my IMEI will never work again on any worldwide network, including the one I'm on now.
Obviously, I should've never gotten into bed with these people.
So even though I believe 100% I'm justified in doing the charge-back... I can understand them filing a claim in court... that is their right, and I suppose I can "fight" that.
But saying they will blacklist my IMEI number... That definitely seems like they're bullying me... So my question is... Can they actually do that? Is there anything I can do now to prevent that? If they do it, will I be able to have AT&T undo it? And will AT&T help me knowing that my intention was to unlock the phone? And any other advice in dealing with this would be appreciated.

Answer 1

http://www.mondaiji.com/blog/other/general/10177-scam-alert-officialiphoneunlock -co-uk/
The Endgame
Mid-March, 2013 I received an email from officialiphoneunlock.co.uk stating that my credit card company had initiated a charge-back.  They threatened to blacklist my iPhone and report me to the authorities if I did not call-off the charge-back.
Here's the actual email text:
We have been informed by our payment processor that a chargeback has been initiated by yourself against the unlock for IMEI:
In accordance with our terms and conditions (see below), proceedings will be initiated in 48 hours for the blacklisting of this IMEI from working on ANY network worldwide, INCLUDING the original network it was locked to. Please note that this is PERMANENT - once an IMEI is blacklisted, there is no possibility of removing this entry. You were warned at the time of purchase of the consequences of filing a chargeback and de-frauding our company.
In addition, if you are based in the UK, we will be filing a Money Claim Online for the cost of the service itself, plus GBP25.00 court fee, GBP25.00 chargeback fee, and £50 administration costs.
If, however, this was a mistake on your part, then you can halt this process is by replying to this email where we will collect payment for the unlock via bank transfer or credit/debit card and immediately halt the blacklisting/small claims process.
Kind regards,
Stephanie
Chargeback Administrator
The Official iPhone Unlocking Team
http://www.officialiphoneunlock.co.uk
iPhone Accessories and Repairs Ltd, a company registered in England and Wales no. 7838094
0121 510 2140
13.1 We will not tolerate any attempts to obtain our services by fraudulent means. We report all such attempts to defraud our company to the relevant credit reference agencies and authorities.
13.2 To combat fraud, we are obliged to log the IP addresses of customer computers at each and every stage of the buying and delivery process.
13.5 In case of any chargeback, the associated IMEI will be blacklisted in the iTunes database, preventing it from working on all networks worldwide. This is PERMANENT.
Then my order status showed this:
THIS ORDER IS FRAUDULENT.
The IMEI will not be sent for unlocking. Your IP has been logged and passed to the card authorities, the IMEI has also been blacklisted within the Apple iTunes database from working on ANY network worldwide.
The cardholder will be refunded in full.
DO NOT PURCHASE FROM OUR WEBSITE WITH STOLEN CARDS IN FUTURE.
Handset Model:
4S
Locked to:
Softbank Japan
14 Mar 2013 13:23:18 - IMEI submitted to unlock server
Approximate Timeframe: 5-10 days - please remember, that when considering timeframes, unlocks aren't processed at weekends.
If the timeframe has been exceeded, it will either be that your handset is barred (lost or stolen) and hence requires a slower method, or one of the reasons below:
Unlocks were offline for 1 month due to the Chinese New Year. Unlocks will start coming through from this Friday on a limited number per day, please be patient.
This made me laugh and served only to 100% confirm my suspicions that this "company" (if you could call it that) is indeed fraudulent:
* This wasn't a business transaction.  Threatening people for financial gain is extortion.  Isn't that a crime?
* Their site says that they aren't responsible for delays.  They'll take your money, but they aren't responsible for delivering the service.  That alone should be a red flag.
* The delay is due to Chinese New Year?  Really??  Here in Japan we don't celebrate Chinese New Year, you dummies.  If you're going to lie, then at least get it right.
* If they couldn't get my phone unlocked in 5 months, how could they get it blacklisted in 2 days?  This is yet another lie, so now they're not just thieves, but liars too.  Much worse.
My Softbank iPhone is just fine, and my money is back.  My phone is still carrier-locked of course, but I learned a valuable lesson