I've been advised to file a support ticket directly on tf2op, just did that.

I got answered.

Originally posted by tf2op mod:

The trade was closed for a violation of the rules, and the trade will not be reopened. Thank you for your report

I do not understand which rules I violated, though, please, can somebody enlighten me?

The closest I can possibly find is:

Originally posted by tf2op rules:

Please do not make trades with...
Links to third-party websites, apart from relevant YouTube or image hosting websites.

But that trade doesn't fall into that category.
People are linking their rep-threads and their steamrep profiles all over the place and suddenly my rep on my SG/t profile isn't allowed?

I'll try to have this thread only, but I'll re-create support ticket on the site if I won't get answered.

Hello, my apologies for the delay. I was not aware of this discussion until I was notified by another Outpost staff member a few days ago. I have personally not used steamgifts.com and made my close reason based on the information supplied in the ticket filed against your trade. In retrospect, I should have checked if it was valid, and I apologize for any issues having your trade closed may have caused you.

I was waiting for a steamgifts.com moderating staff member to answer whether or not users are allowed to ask for trade feedback from trades which did not originate from threads posted on their site, but have yet to get a response. I have read their rules, guidelines, FAQs and anything else which may provide the answer to this question, but I could not find an answer which stated whether or not it was allowed.

If I am told it is allowed, then I will be happy to reopen the trade for you, if you would like, or you could simply make another one with the same formatting and link.

Again, my apologies for the potentially false closing of your trade and even more so for the extended period of time it has taken to handle this issue.

Originally posted by Baloo:

I was waiting for a steamgifts.com moderating staff member to answer

My oldest "support" ticket just 1 year old couple of weeks ago, so it's not surprising they didn't reply.

I made a thread there where I was redirected to an older SG stuff comment, which, surprisingly, was even in "Trades" section, that's probably why I failed to find it through Search bar.

http://www.steamgifts.com/go/comment/FEyOM8C
↓
http://www.steamgifts.com/go/comment/4phy9zn
↓
http://www.steamgifts.com/trade/af3y1/

Old trade http://www.tf2outpost.com/trade/24105499
New trade http://www.tf2outpost.com/trade/26188114
If this issue is resolved, would be cool if it'd be possible to reopen my old one and close the new. Or grab formatting from the old and paste it into the new.

I have finally gotten an administrator's response and have been informed it is allowed. Your old trade has been reopened. If you have any further questions or concerns, then please let us know.