If this is for real why press & interrogate customer service/GA's over a purported mx delay?

Did further questioning make their answer change? Did pressing them about the issue change their answer and did they ultimately admit the delay was to let the flight crew sober up? Was interrogation enough? Was the next step "water boarding?"

Seriously if an mx delay is going to be that big of a deal it sounds as if the OP is in dire need of taking a maintenance/operations tour at the next CO Kellner/Burri event, and see what this airline and the most professional men and women in the industry go through. I think you'll find they're really focussed on staying flying and maximizing profit by trying to reduce delays.