Hello and Welcome KY,
If the Pain Contract that you signed states you must come in for a pill count when called - then yes he can discharge you. The real question is will he discharge you. Let's hope he understands your situation and will take that into consideration.
I know it doesn't seem right when you have no transportation but sadly that's the rules. If he doesn't dismiss you I'd ask to have your contract revised. Maybe the two of you can work out something that will be acceptable to both if you. This will give you some peace of mind.
I'm not certain if ADA comes into this equation. It may. I would remind your PMP of that fact - and again revisit the contract. Do you have access to public transportation? If so and it's not an impossible feat for you to take c bus or cab you may not have a lot to stand on - but it's sure worth a try.
Please keep in touch and let us know the outcome. I hope your concern is for nothing. Let's hope your PMP will understand. I'll look forward to hearing from you again soon.
Take Care,
~Tuck
Did you explain you don't have a car when they called you? If not, I would call right back and say I'm working on transportation arrangements but I don't know if I will be able to find some today. Is there anything else I can do like send a picture of my remaining medication with a copy of today's newspaper in the picture? Ask them what they would recommend.