The HV battery should be able to hold its charge for 2 months if you had disabled the SKS system.. 88 days is probably pushing it (that's 3 months).
Wouldn't hurt to try though. Hit the Power on button and see what happens. If you can't get it into READY mode, then yea you need to get it to a dealer to charge it up.
If it does go into READY mode, then you should drive it for about an hour so the HSD system can use the gasoline engine to charge up the HV battery.
Good luck.
