It is really SO SO hard....
But, if this teacher and this school do not seem willing to bend on Cursive and some of these other issues, until you have a full and objective eval, that would be the deal breaker.
PS: My son was also ambidextrous.
There are only like, what, 4 months left in the school year...
I would request a meeting with the teacher and with adminstrative staff (Principal?), in writing (important to have this in writing if an IEP becomes involved) and request that any 'undue' pressures and expectations be removed, on any of these issues that might be due to underlying deficits/disability, until this eval can be done.
This is what I did with Math, with my son.
He was diagnosed with significant to severe Mathematical Reasoning deficits. Which are common with his Visual Processing disorder.
I basically told his first grade teacher, at about this time of year... maybe March... that I wanted the pressure of all math taken off his shoulders.
No pressure on performance, grades, passing/failing. And that I was in the process of getting a full eval, and would be awaiting results.
Incredibly, this was agreed to.
But, unfortunately, by the end of the year, I basically stopped sending him to school for a few weeks, as things had gotten so bad.
I then scheduled a full IEP meeting for when I finally received all of his eval results.
He was then scheduled to go back to school, on a full IEP, into second grade.