Surgery on Ankle.

I had surgery about two years ago on my ankle. currently there is a bolt going through my ankle atm and I didn’t realize it til now that I believe the lack of mobility from the surgery is preventing me from doing deep squats. When I try to attempt deep squats the ankle that had the surgery would want to be forced on my toes and not my heels or the balls of the feet. This doesn’t happen with my non surgical foot.

I had a condition called Tarsal Coalition (fusion of two joints) so basically what the doctor did was cleaned out the tendons inbetween (that was causing the pain) and permanently fused the bones together so I wouldn’t get any pain anymore. But from the results of that surgery I am not able to move my ankle in a pronation or supination movement. The only movement I have is dorsiflexion and plantarflexion. And the movement that I have isn’t all that much. I am unable to flex my calf fully on the surgical ankle as well (i knew about this one after surgery). Well here is a link to the picture of the bolt within the ankle

I was wondering if there was any way to develop the calf of the surgical ankle (i’ve measured my calf and its roughly 3 inches in circumference smaller than my other calf). And would I still be fine doing squats even if I barely hit parallel?