Jump starting from a Hybrid is a definite no-no as the electrical system is not designed to provide the required current output (typically a short duration of several hundred amps to crank an engine), the 12V battery just boots the electronics with the power to crank the engine coming from the Hybrid battery.
Jump starting from another vehicle should be ok, probably don't even need the engine running as you just need sufficient power to boot up the electronics.
The third scenario would be a flat Hybrid battery (eg vehicle left standing for a long duration), I assume there is a dealer procedure for this.