Not really, but he could evaluate what he believes the compensation event should have been in accordance with the contract. These are not subject to a revisit after implemented - only through adjudication.
PM assumptions come into play much earlier in the process. The PM states when requesting the quote what assumptions they should base the quote upon. Practically, I recommend if a Contractor is thinking of putting their own assumptions in a quote they should get the PM to agree them in writing before the quote goes in, or simply price the risk. Any such Project Managers assumptions can be revisited as a new CE (60.1(17))