Well - assuming it truly is incorrect - you simply need to "unlink" the one connection that is linking the good aprt of the tree to the bad part of the tree - probably just one connection/reltionship - and all the ancestors of that bad connection will go away (disappear) with the change - though such people will still be in the database - just that they will be unlinked.
can you share with us the PID of the peopel for which the exact relationship is incorrect.
For starters ...
I am so glad that you used the "Remove" an entire section; as opposed to, "Delete" ALL the individuals/persons.
So many new/inexperienced Users/Patrons think that they NEED to entirely "Delete" the 'wayward' individuals/persons from "Family Tree" of 'FamilySearch', instead of just "Removing" them (ie. the 'wayward' "Branch") from the User's/Patron's "Ancestral" lines.
That said ...
That all depends on HOW and WHERE the incorrect (ie. 'wayward') link/connection is in your "Ancestral" lines in "Family Tree" of 'FamilySearch'; as, technically, we DO NOT a 'Tree' in "Family Tree" of 'FamilySearch' ...
We do not have our OWN "Tree" in "Family Tree" of 'FamilySearch'.
We ONLY have "Branches" (ie. Ancestral" lines), that are interconnected, in this SINGLE "One" World "Tree", for all of us, that is "Family Tree" of 'FamilySearch'.
That said ..
You can "Detach" (ie. "Remove" or "Replace") the 'wayward' "Branch", it just depends on whether it is that it all starts, at, an Individual/Person; or, a "Couple" ...
For starters, here are a couple of "Knowledge Articles" in 'FamilySearch'
A person in Family Tree has the wrong spouse
How do I correct parent-child relationships in Family Tree?
I hope this helps.