A verify command in CookOnTheFlyServer is checking the wrong condition and causing cooking to fail for patches that are based on a previous release or have had something removed from the build.
The verify is in CookOnTheFlyServer.cpp line #6062 (in 4.18) and is:
This Verify triggers if anything other than null is returned. This should be the opposite, so that it only triggers when null is returned.
No reproduction at this time, code issue
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-55015 in the post.