As a bicyclist you (should) pay very close attention to what's going on in the right turn lane, are they slowing down? Have they seen me? *CAN* they see me? And trust me, I assume that all drivers are idiots playing on their phone will trying to eat a sandwich - having a indication that the driver turning right is absolutely blind and oblivious to my presence just means I can react a second earlier.
Perfect! Since they are playing on their phone, even if their mirrors were intact, they would not be looking at them. Since your assumption of the driver's habits is the conservative one, it doesn't matter whether their mirror is a mirror, a camera, or a shattered piece of useless plastic.