I'm not a PT but have personal experience with a similar injury --

Just wanted to add some thoughts on healing time and pain & ROM. It can take a LONG time to get back to pre-injury condition. I still sometimes limp if I am tired or not concentrating on how I am moving (my walking mechanics weren't great pre-injury, it's just something I am always working on).

I had to cut my PT short after only three weeks, because I couldn't pass up an opportunity to study abroad that year. I took my PT homework on the road and followed up with my PT after I got back. On the one hand, maybe it wasn't ideal to have that break in care, but on the other hand, having that elapsed time gave us some ideas as to what was working and what else we needed to focus on.

About two years after my injury, someone told me that where you are after a year is where you're going to be. Thank goodness I didn't get that memo!
At that point I was still in pain on a daily basis, still had something of an old-person shuffle when I first got out of bed in the morning, but I was still making progress! It took that long for me to be able to do some things that I had not been able to do since getting hurt; it has probably only been in the last year where I feel like I'm out of injury mode and more in daily maintenance mode.

For a while, to get on my bike I would stand on my good leg, lift the bad leg up, hug my knee to chest and guide my ankle over the top bar. For my first year I favored my folding bike with its low stepover.

The best thing for me to get my ROM back after I was done with PT, was to keep on moving. I had a desk job but tried to move around as much as possible. A good part of that is knowing when to work through some discomfort and when to ease off so as not to make things worse.

I had done a lot of pilates before my injury so I used that as my baseline for what I wanted to be able to do after my PT discharged me, in terms of strength and flexibility. I had an instructor who also had a PT background and she helped me to adapt exercises for my limited ROM and gave me exercises that would help improve my ROM.

This month is the 4th anniversary of my injury. It's been a 2-steps-forward-3-steps-back kind of year. I can do everything I was able to do before my injury with no restrictions. I have my pre-injury ROM but often feel clumsy when I am moving around. My mind-body awareness of the injury site is a daily thing. I don't go a day without thinking about it. Add that to brushing my teeth and cleaning my contact lenses: I need to stretch, massage and move in order to get through my day.

Lying to his PT is a bad idea. Having a frank discussion about expectations and goals would be a good one.