They do provide services to high school students. You are thinking of a different program that does 3-5 year olds
After age 5 its done by the school district rather than private providers. It is not called SEEIT, It has various names depending on grade level.
I never said tution reimbursement is guranteed if you have the IEP, I never even spoke about the issue, but since you brought it up, Its possible if you hire a lawyer to get YESHIVA tuition reimbuirsement, but you need the IEP to even attempt it.
Of course I havent done a evaluation of the OP. You cant do one over the internet, you need to monitor the student in the classroom to do it and they have several experts doing it.