In your first post, you said the Vet said it was Grade 3+
IMO - This is serious and IMO this needs surgery.
There are only 4 Grades of LP and the higher grades don't correct themselves.
LP does only get worse. When the patella luxates it rubs back and forth and during this luxation cartilege is being worn away. This cartilege can not be replaced or repaired

So by having surgery to stablize the luxating patella you will stop the wearing away of the cartilege.
If you leave this LP alone, somewhere down the road, he will start to limp and be in pain or be laim. Arthritis will set in.
I know that the LP surgery is expensive, but it is worth it in the end.