No, they don't cover all tests.
They will cover most of Igenex's test. I paid $65 of the $210 in 2015 for Lyme IFA screen (#230,) Lyme western blot IgM (#188,) Lyme western blot IgG (#189.) I think their prices have gone up and they have new tests since then. It would be a good idea to call them and see if they can give you a ball park (since they will say they can't guarantee that's what you will be required to pay) on the test(s) you want done.
That's what happened when i called, they seemed pretty nonchalant about
it. Pretty much said "whatever your Medicaid covers, i dont know"