As you say, for those of us who can only observe in the absence on any meaningful statement from FINRA, these are uncharted waters. According to the company, the old TA refused to hand over certain records two years ago. We don't know what those were, and whether they were of critical importance. But the company would still be to some extent culpable, as it's the TA's employer. If there was a problem, it should have asked someone--perhaps the SEC, who regulates TAs, or DTCC--for help.
Obviously some significant problem WAS brought to FINRA's attention; one significant enough to persuade them to halt trading.
We don't know what it was, but I very, very much doubt it had anything to do with George Sharp.
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