i'm back!
So, as a general rule, standardized, norm-referenced instruments like the WJIV can only be used for their normative qualities if administered under standardized conditions. You don't need a quote from the manual (although fwiw, here's what Riverside says about using accommodations during testing with the WJIV:
https://support.riversideinsights.c...accommodations-can-i-use-during-testing-) to support this well-established basic principle of normative assessment.
I understand the argument that they gave accommodations for achievement testing because they wanted to assess writing separately from motor speed (although I think many of us would have chosen a different method to assess this), however, given that he has historically been identiifed as physically impaired, there should have been assessments in his area of identified or suspected disability (ie, physical impairment--in this case, occupational therapy evals and assistive technology evals).
Another factor that the district might want to consider (which is more in the category of enlightened self-interest) is that, in the absence of documented disabilities, the College Board may not allow typing as an accommodation on the AP exams, which may very well lower his (highly likely to be) strong contribution to their average AP score performance in a way that is disadvantageous to their district scorecard. Note: the WJIV sentence writing fluency task is one of the types of tests (actually, the WJ is named) used to document a disability for purposes of qualifying for the typing and extended time accommodations, so obviously, using the accommodation on the test invalidates its use for that purpose.
FYI, there are other instruments that have writing fluency measures on them, so if/when the IEE is approved, there will still be ways to document his actual level of development.
So how is he actually doing with AT these days? It sounds like his typing has improved some.