The parliamentarian is there as an advisory position, they have no authority and Congress can choose to ignore their recommendations.

Can the Senate Ignore the Parliamentarian’s Advice? Yes. The presiding officer can choose to ignore the advice of the parliamentarian on any matter they choose, which has happened several times before.

The parliamentarian exists to advise the chamber on existing procedures, but it is the presiding officer’s duty to make rulings. However, any senator may raise a point of order challenging the ruling of the presiding officer for not following the correct procedure. The dispute would then be put to a vote of the chamber. Ultimately, senators themselves are responsible for deciding the outcome of all parliamentary questions, even if they go against standing rules and precedent.

https://bipartisanpolicy.org/explainer/what-is-the-role-of-the-senate-parliamentarian/