I see two ways this should go:
A. If the check did not clear, the seller should initiate the insurance process and recoup what he lost.
B. If the check did clear, the seller should also initiate the insurance process (or at least give the buyer everything he needs to do it) and have the insurance pay out to the buyer. Unless the seller is absolutely certain that the buyer is lying, then why not do this?
A. If the check did not clear, the seller should initiate the insurance process and recoup what he lost.
B. If the check did clear, the seller should also initiate the insurance process (or at least give the buyer everything he needs to do it) and have the insurance pay out to the buyer. Unless the seller is absolutely certain that the buyer is lying, then why not do this?