Basically, just politely insist that you think he qualifies under Section 504, and steer all inquiries about accommodations/needs back to that. It's not about whether a student NEEDS a plan or designation, or any particular accommodations. All of that has to come after the determination of eligibility to begin with. If he isn't eligible, he's not entitled to anything in particular beyond what the teacher does (or withholds) for any student upon whim or demand.
So discussing RTI (or R to begin with, actually) is premature unless they think he's eligible.
"Oh he doesn't need a 504 plan,"
Well, but if he's ELIGIBLE for one, that's what you want (trust me, you do).
Largesse is lovely, but children shouldn't have to feel at the mercy of anyone in getting access to the education that they are entitled to under the law. Don't place yourself in the position to reinvent the wheel every time you get a new teacher, a new administrator, or move schools. Some of that is unavoidable, to be sure-- but kids with disabilities are particularly vulnerable to those kinds of changes without any formal documentation in place. He's entitled to it, and hey-- maybe that magical bit of paper says that they'll do whatever policy happens to be right now-- that's fine, too-- but that bit of paper says they'll KEEP doing it for him even if policy shifts. Important, that.
