Going to be honest here, not sure if this is a PTR bug. I will also admit that statistically it is possible I have been unlucky.
However, with Loxmere not spawning 15 runs in a row on Elite, the odds of me being unlucky are starting to swing towards ‘unlikely’.
Grim Tools still has him spawning on Elite, so going to assume that if it was a change, it was a recent one. He does still spawn on Ultimate.