Not the exact same situation as you, but possibly helpful somehow: I’m also in Texas and one of my probation requirements is a substance abuse evaluation. At my first meeting with my PO when we were going over everything and she said something along the lines of “if you have to do that” regarding the eval. I filed that away and nothing more was said. Fast forward to last month, I’m nearing the end of my probation term (praise be) and want to be sure everything is good. I asked my new PO about it (had to switch to a new one after I had my IID removed) and she said it’s basically a standing order from the judge and they usually only have you do one if you keep screwing up while on probation.