I still have Bitcoin in there. @Tillkoeln, if you are around, please solve this problem ... it's not looking good ...
Alright guys I want to update you on this matter, one month later. Around the same time as I noticed my account being locked I got a message from TillKoeln where he accused me of hacking his site, because apparently I am using the same browser and IP as some attacker (I'm using a VPN). Of course I had nothing to do with it and after a solid 2 weeks of discussing they unlocked my account again. @Mr00HasH was very helpful and responsive on this matter, I think he's a good guy who is legit trying to help.
Then I tried to withdraw some BTC (a small amount) but it got stuck ("error") because apparently the hot wallet was empty. Mr00HasH said he can do nothing about it because TillKoeln is the only person who has access to wallets. One thing I noticed is the high withdrawal fee of 0.00075000 BTC, which was apparently because Bitcoin fees are so high. Fair enough. I asked them to cancel the withdrawal so I can withdraw my full funds all at once to save fees.
Another two weeks later (a few days ago), TillKoeln became active and authorized the withdrawal instead of canceling it. The transaction was pushed to the network, but the actual transaction only used a fraction of the fee they charged me for it, 0.00018000 BTC. Result: TX is stuck in mempool for days, still not included. Meanwhile, on the site the withdrawal is shown as "completed".
Summary:
- There were apparently attacks on the exchange, owner seems a bit paranoid at this point
- Support response times of multiple weeks, but things were eventually settled, yet
- Charged withdrawal fee is 4x of what is actually used as the transaction fee
- Actual transaction fee is way too small
- Withdrawal is marked as complete even though the transaction wasn't included on the blockchain
At this point I have come to the conclusion that Unnamed Exchange and TillKoeln are not scammers. They simply don't know what they are doing and unable to deal with the challenges faced. I think it's quite possible that in some cases they did not intentionally steal money but just accounted it incorrectly.
Still hoping to get my money out eventually. I'll report back in a month.
Edit: Transaction was included after 4 days!