This reminds me of the period when mixers were banned/closed-down by the Joe Biden administration, a colleague who mixed a few coins with Sinbad and transferred it to his Binance which later got locked. He was sent notification to provide information about the funds which still got confiscated at the end. That was how he got to abandon the account as it has been flagged to have been used to receive illegal funds which in real case was illegal but just because of the channel the funds was received.
Since you made mention of Sinbad, this reminds me of the people who suffer and face some questioning from exchanges. I was part of the signature campaign back then before I left the campaign, but most of my fellow participants who used an exchange address to receive payment directly from the campaign escrow wallet were asked about the source of that money, which was due to the case at hand in respect of the band mixer.
Both those whom I know had funds in their account before they were asked to explain and those who have withdrawn their funds all were set free, and their account was back to normal after they provided a detailed explanation of how the inflow of that money came about, which I believe is how things should be handled professionally.