But all it obligate for Congress is that: " Congress shall #DecideTheIssue, assembling within forty-eight hours for that purpose if not in session. " None of this is automatic, and it places NO obligations on " #PrincipalOfficers of the executive departments"
I read #NoObligation for: " #PrincipalOfficers of the executive departments or of such other body as Congress may by law provide" to do anything, in the text. constitutioncenter.org/the-constitu...

The 25th Amendment of the U.S....
The 25th Amendment of the U.S. Constitution

SECTION. 1. In case of the removal of the President from office or of his death or resignation, the Vice President shall become President.

National Constitution Center – constitutioncenter.org