Good point, I can increase the values of the resistor divider to reduce the current and voltage if needed. I did have the monitor pin on the Vcc side but I thought @Dave_Lowther 's suggestion was a good one as it would buy me some more time after trigger goes down as the cap will discharge from 12v instead of 5v.
I don't think this will damage the chip but maybe it could boot incorrectly. Dosent the Attiny have an internal diode up to Vcc on these pins to prevent damage?