Thanks Mr. Legs! I looked at the DRIVE SIDE cups on three other track bikes that all have the same Phil Wood BB:
one is in all the way, one a mm of thread exposed and the third has maybe 2mm exposed. This one, that came undone had at least 3mm exposed when set up. I'll have the mechanic re-do it and chase the threads but what goop should he use: loctite again, the blue Phil Wood stuff or something else?

Thanks for everyone's help. I'm feeling better...