I meant settlement between the two intermediaries. I intended to be ambiguous as I don't really care how loss for the firm can come about. Wrong use of the term.
Large brokers have collectively decided they're supposed to do AML checking on any OTCBB transfer in after the IBKR fine. That's a manual process that costs serious money and is annoying for all parties so easier to just disallow the transaction. Some smaller brokers haven't got the memo yet. SEC intent is to basically regulate OTCBB to death and they're succeeding. Kind of funny in light of wild west in shitcoins and crowdfund capital raises being legalized.
An OTCBB dark stock changed my financial life so I'm sentimental. Ran across a company trading at ~1x FCF and bought as much as I could. >10x return when it was acquired and doubled my capital base.