You have my sympathy. Stripped threads in aluminum is a real PIA. If the bolt threads are full of aluminum, a retap is out of the question, there's no meat left to retap.
A helicoil will require removing the side cover. Then you have to make sure there's enough metal there to allow a helicoil. There are some liquid metal/epoxy materials on the market, but you have to squeeze them in there while allowing the air to gat out, then after they dry, drill and tap them back to original. I haven't used any for this purpose so I'm not familiar. Hopefully someone will come along here with some new improved fix...
If all else fails ask the dealer....
Good luck and sorry I can't be more helpful...
