Your new mortgage will probably be denied once the new Lender learns of the mold issue.
Remember none of the other competing bidders knew of the mold issue, and you were out-bidding them . . . . what would they have offered had they known of the mold issue.
Now that it is known, the Bank will have to disclose it in soliciting future offers.
I think you're too emotionally involved in this property and ought back off and look at it objectively. In doing so, I think you'll walk . . . . or get a major concession to deal with the mold issue BEFORE Closing.
I think you left the following questions outstanding:
Who drafted the P&S with dates like that? The Bank?
Do you have an Agent working for you? Or an Attorney?
Who's interpreting the P&S for you?
Mold mitigation can get very expensive . . . . and no one can give you an accurate quote of what it'll be until they actually start the job and see how far it has progressed. Many will give you a bid (couched in terms that allow for escalation depending on their discoveries) because they want the work.
If you're not in a rush, I'd back out and watch from the sidelines; see if the Bank mediates the mold or discloses it; and possibly come in later with a new Offer after the dust has settled.
Don't allow them to hold you hostage to your emotions . . . . and don't participate in withholding information about the mold from your own Lender . . . . they won't forgive you, and you won't forgive yourself.