Craig did not discredit Paul in any way. He is saying that rapture fiction is based upon a incorrect interpretation of Paul.
Yes, the Rapture/millennium theology misinterprets Paul and it also skips around and misinterprets some Old Testament passages and uses the Old Testament to interpret the New Testament. It is quite a patchwork. It should give people pause that while Christians from early on had somewhat differing views of the end times, no one knew anything of the Rapture and Jesus’ secret or partial return and dispensations until this system was first taught 200 years ago. This system was an odd, minority view even among Baptists until 100 years ago when the Scofield Bible made it popular.
I have nothing against the rapture theory and it appears that
Paul was talking about live people meeting the Lord in the air
in thesolonians.
However in 1 Corinthians 15:35 to 58 Paul discredits what he said
in thesolonians, so it appears to me that no one except Paul is doing
the discrediting.