BlueDevil Products Red Angel A/C Stop Leak and Conditioner

The evaporator in my 2005 Prius is leaking. The price to fix it is $1614 because the whole dash has to come out. Will this stuff work on evaporators?

Is there a way to purge the air from the hose before putting it in?

Do you use the whole can ?

Can you add this after you have recharged the r34?