There is no law against holding your money if you don't give them ID.
{{citation needed}}
There is a law? Wait, where?
{{citation needed}}
Are you insane?
Do you think there is not a law agains you holding my money?
Like, in, I don't know, theft?
Either there is a specific clause claiming you can hold my money, or you are breaking the law.
Requesting ID and giving the money after ID is provided in order to not break the law (if you just give and take money, even after they file a support ticket, it's still breaking the law if you don't follow the proper procedures) =/= stealing.
There is no requirement for MSB collect ID before returning funds from an incomplete transaction. However you are asking someone to disprove a negative. The regs for MSBs are publicly available you claim the law requires them to "hang on to" = "steal" so provide a cite for the reg requiring this activity.
As someone who has attended BSA training I will save you some time. There is no requirement, no obligation, there isn't even the right for a company to "hang on to funds". The company can refuse the transaction at which point they are required to return the funds. If the company believes the transaction is suspicious they are obligated to file a SAR. If the company knows ID will be required they are obligated to collect that PRIOR to starting the transaction.
The company asking the client to report the transfer as fraudulent with their bank in order to have funds returned should set off some alarm bells. Does that sound "normal" to you?