Huh, this is an interesting development:

Several hours after publication of this article, Vast released additional information about the origin of the planning document. The company stated:

The Mission Integration and Operations Management Plan was provided to Vast in the normal course of business by a subcontractor that supplies services to Vast and Axiom, using standard documentation adapted from prior missions, as is common practice for NASA private astronaut missions. The version provided to Vast included material carried over from an earlier Axiom mission.

Within a day of submitting the document to NASA, Vast proactively informed NASA that the document needed to be corrected and resubmitted a revised version the next day. When NASA later asked us to take additional steps, we did so immediately, and we have cooperated with NASA throughout.

Vast did not take anything from Axiom, and any suggestion otherwise is false.

Can the subcontractor that "included material carried over from an earlier Axiom mission" be anyone other than... SpaceX?

This would imply that SpaceX failed to perform the Ctrl+H find-and-replace, but also that no one at Vast actually read the document before passing it on to NASA... which would not be a great look for either company...