Yeah that's what I've found in my research. My shoulder for my most pressing issue so if there is any chance that it makes a difference then I will stick with injecting there.

It would be awesome if it helps with a (suspected) meniscus tear, but that is only a minor issue for me compared to the shoulder tear.

No changes yet but not expecting any either.

Yeah I wouldn't try and inject in or too near a joint but that's just me. Stick in the muscle or fat and you're good to go! Best of luck.