When SR PFD showed up on (were placed on) the BS as a stockholder liability what was the offsetting asset Debit/
I assume it was an exact same dollar amount deposited to "cash" and or booked as some sort of holding/reserve?
I see it the same way. When the senior preferreds were issued they were added to equity as a positive number. FnF gained that amount of cash from Treasury and added that to assets (cash), keeping the books balanced.
That means if the senior preferred line is deleted from the balance sheet it actually drives equity (and thus net worth) down, not up.