If a Compact of Association to which a member has made application, and been admitted, contains clauses permitting such forceful expulsion -- then yes, of course such a member may be expelled according to the terms of such clauses.
If not, then of course it's entirely up to the member himself as to whether or not he wishes to continue his membership in the club.
OK, what clause of the Constitution says that a state cannot be expelled against its will?
If a Compact of Association to which a member has made application, and been admitted, contains clauses permitting such forceful expulsion -- then yes, of course such a member may be expelled according to the terms of such clauses.
If not, then of course it's entirely up to the member himself as to whether or not he wishes to continue his membership in the club.
When our Constitution was ratified by the first nine (not 13) acceding States, the remaining four non-ratifying States were "turned out of the Union." That is historical fact - denied by people like N-S, but historical fact nevertheless...