I would not teach anything in any twin without a few hours PIC in make and model, even though the regs allow it.

Did you gget hired to teach in the duchess? What did you discuss with the boss regarding the 5 hours. Any sane flight school would give you at least 2-3 hours of checkout in a type you're never flown before. Maybe they can do that and give you a steep discount on the remaining time.

I once worked a school that gave such good employee discounts that it was practical to take a twin on a fun weekend getaway.