ALWAYS remove & refit an automatic transmission with the torque converter correctly installed into the pump of the transmission. NEVER bolt the converter to the drive plate & fit the 'box to it. I replace 2-3 broken pumps & converters a month in transmissions where they have been incorrectly fitted.
You will of course get away with it on rare occasions

& I'm sure someone will now pop up here & say that is how they have always done it & never had a problem etc etc.
I would hope they cleaned the oil cooler & lines out correctly as well as the sump & filter. Debris from a previous failure that was in the oil cooler has caused the demise of many a replacement unit when not cleaned out properly.