I answered in the other thread that it did take longer than the vet said for my Havanese to recover from his injury, and we had to control his access and surroundings because he didn’t self regulate the way the vet expected. But I didn’t see that he runs outside and not inside. Mine did self regulate to a degree, more than I expected, because when DH first told me the vet said he would regulate I was completely skeptical, just knowing Sundance! He did wait to be picked up for the stairs and lifted onto furniture

But he’s used to being picked up frequently and he already knows to sit and wait if he wants to be picked up. Usually when he pushed himself too hard is when he wanted playtime and attention, which I think is pretty normal in a breed that is so people pleasing, and possibly underestimated by the vet. We worked on giving him more calm playtime on our bed and carried him in the hall or on the stairs so he wouldn’t take off running, because he would hurt again afterwards. We didn’t take him on walks at all and just barely started again a couple of weeks ago.
I don’t know anything about injuries other than my limited experience with a very vaguely diagnosed injury at Thanksgiving, but I do wonder if your Havanese is more impulsive playing outside and is excited and happy so he’s ignoring his injury during playtime and it hurts when he comes inside.
Hopefully you’ll get medical answers soon!