There is no interpretation involved. The contract is clear. It says approve, not appoint.
Now, I agree. The end result is the same. But getting to the end result is different than what Lead said.
It may be that way in his local, and maybe yours, but that is not the norm and not what the contract clearly says.
The local does not come in and tell UPS that John, Paul, George and Ringo will comprise the safety committee.
UPS inquires as to who wants to be on the safety committee, or John, Paul, George and Ringo tell UPS that they would like to be part of the safety committee.
The local now approves whether all of these employees, some of them or none of them will be on the safety committee.
Again, the end result may be the same as what you describe, but getting to that end result is not as you described.