You would want to contact your insurance (Medicaid) and ask to speak to a care manager. They may not pay the fee if the service is an excluded benefit. There is no way around that.
On the other hand, if this is a covered benefit (some insurance generally pays for medication but not the doctor's visit) and if that is the case, you will be responsible for that payment. The clinic also must be on the Medicaid panel for payment if you have coverage for suboxone (it may be out of network )
The only one that can assist you with this is Medicaid (your insurance carrier since they are the payour) You want to find out if the benefits are covered and if they come out of your medical or mental/substance abuse portion of the coverage. If the benefits are not covered, they won't pay no matter what. You can ask them in that case, should you go into withdrawal, what would be the next level of care you're going to be able to access that they cover (rehab/in house detox, methadone, etc)
You may interpret it as you wish. They should not stop your medication cold turkey or should make provisions for you to obtain treatment elsewhere before they discountinue seeing you. But, the fact remains- they did it to you. A claim is usually denieid for these main reasons 1/ the service is not a covered benefit, 2/ a person had maxed their benefit for the year, 3/ the service for which they are billing does not meet medical necessity criteria 4/ services were obtained by an out of network provider
Whoever is in charge of approving your appliation would be the main entity to deal with. If your medicaid covers this benefit (and you have to make sure that they absolutely do both medicaiton and doc's visits) then you can always appeal it. Usually you have 3 times to appeal the insurance's decision.