Floating the 12V battery should be fine. The hybrid battery should be ok sitting for a few months. I would park it with a high SOC showing as it will loose about half of its SOC sitting for a few months.

The Toyota Camry Hybrid Emergency Response Guide states on page 13:

High Voltage Safety System

Positve and negative high voltage power cables connected to the HV battery pack are controlled by 12 Volt normally open relays. When the vehicle is shut off, the relays stop electrical flow from leaving the HV battery pack.

WARNING:
The high voltage system may remain powered for up to 10 minutes after the vehicle is shut off or disabled.