Of course not. They lent against an entire portfolio. If they have to order 10s or 100s of their own, third party appraisals for each application, they have to pass that cost to the borrower. The borrower already shouldered this cost by paying a third party to compile the financial statements. If the bank tries to charge the borrower for this, the borrower would go to a bank that does not. The borrower also would be burdened by the extra time and would go elsewhere.
No, this is the role the third party accounting group plays. In this case, Mazar's. It's a good system that keeps the money flowing. And, as with all lending, the burden of accuracy of the submitted materials ultimately lies with the borrower. The borrowers attest to this under penalty of law when signing the application and do so again at the closing table. Unless it can be shown that the third party accounting firm committed fraud or an egregious mistake, the burden of accuracy and honesty lies with the person signing this attestment. The moment Trump signed that application and submitted the statements compiled by Mazars, he broke the law. Then he did so again at the closing table, when signing the closing documents.
In this case, Mazars dropped Trump immediately and publicly stated that the financial statements they compiled for him cannot be trusted, which was of course due to Trump breaking his agreement with them by giving them inaccurate information. And as ordered by the courts, these statements were turned over.