I can see into the lower hole, and it seems fine. The upper hole however I cannot see into it and poking it with a stick feels like it may have the old bolt sheared off inside.
What I tried is loosening the front engine mount and then putting a piece of wood so I could jack the right side using the big flat area where the trans and engine meet. It got the holes to align more or less but very frustratingly I couldn't get the bolt to start threading. Cue several hours of going back and forth, adjusting the jack a little, checking the hole with a stick, and trying to thread a bolt in.
Considering that the car has been running with just one bolt for who knows how long, I'm thinking two out of three bolts should be fine until the engine needs to come out of the car. Does this logic seem sound and does anyone have an idea for removing the broken bolt without pulling the engine?
Diagram

Lower hole

Upper hole







