1994 Acura Integra timming?

Last year I had the water pump, timing belt & tensionor and all other belts, as well as distributor cap & rotor, plugs and wires replaced. The was running great and a few days ago a noise started to appear--mechanic said it was either water pump, idler pulley, or damper pulley. Pump that was installed last year was leaking so he replaced it, and the timing belt (he said the one from last year had a slight crack in it) and he replaced the idler pulley and valve cover gasket. When he took it out for a test drive the car stalled at the end of their drive. He said they took it back to the bay and ran it for a while and it died again. I suggested they had the timing off and they said they took the valve cover off and re-checked the timing and it is okay, and they say it may be that it needs a distributor. Are they screwing w/me or just don't know what they are doing? Any suggestions/ideas? Thanks for your help.