The ejection line could be rerouted slightly. Not really a big project to do after the fact. Some fittings and the proper glue.
The access hatch could be beefed up mass-wise and have a gasket, so the pump noise might be very manageable, or completely eliminated.
You also might want an alarm on the sump pump, and/or a water back up pump system.
Other issues you might need to work around, include any waste line cleanouts, where they exit the basement, electrical cabinets, and often support columns, along with
HVAC and support joists.
If each office is 11x11', then how does affect the space above? But the correction of the mis-measurement is a really nice plus for you, if that upper space is even wider.
That might let you slide the whole theater forward and simply host the sump pump in an equipment room.