That is a great question about who sets the rules for delisted stocks.
The only thing we know is that the SEC accepted the 'offer of settlement' to delist the company, plus the SEC didn't go after the company for fraud.
Your observation about the current share structure is valid, but that share structure was 'on the record' before the company was delisted.
Liquidating shares means the current holder gives them up, and somebody else gets them. Some brokerage firms offer liquidation as a service to their customers, but what they do with them is up to them. I haven't actually read anything about what is done with them in those circumstances. From the customer's point of view the brokerage simply provides the record needed for IRS tax write-off purposes, to prove that the shareholder abandoned ownership.
What seems to be true in the case of Schwab is that a "vendor' has approached them with an offer to buy all shares that anyone wants to liquidate. That is far more eyebrow raising than just the situation of a brokerage making liquidation available as a service
As you ask, why they'd want the shares given the current share structure only raises more questions.
