All three branches of the government are beholden to the Constitution as a whole, and to each other based on the Constitutional roles and their expressions of their roles.
All government actors individually are also responsible to the Constitution and its expression by all three branches first, before any loyalty to anyone else. In the same branch or not.
Even before the current top office holders of the executive branch, congressional majorities, or Supreme Court justices.
Saying that a President’s personal interpretation of Congress’ laws or the courts precedence, completely overrides any individual executive employees good faith understanding and responsibility to the Constitution, laws, and judicial rulings is madness.
There will be disagreements within a branch that will need to be worked out. The president certainly has more power and deserves special respect. But his helpers must stand firm with the constitution first.
Settling Constitutional level disagreements within a branch is a desirable process. The president, and all government actors, need pushback when they start running into the weeds, and vetting when their take seems Constitutionally risky or outright invalid. Taking into full account all valid standing orders, laws and rulings.
The Presidents most important advisors are subject to Senate approval precisely because they are supposed to be loyal to the Constitution and laws first.
If the president says he believes arresting disagreeable members of the Supreme Court is Constitutionally supported because yadda, yadda, yadda, you don’t do it.
If the President directs the Vice President not to certify an election, because he interprets that role as active and worthy of pauses and delays to settle issues the President deems Constitutionslly important during an election…
But you the Vice President, after careful thought and consultation believe your role is ceremonial, you fulfill the ceremony.