I have been down this road 3 times and am still on this road now. My oldest had an IEP when she was in school, my #3 has a 504 and my #4 has an IEP. I have fought for the evaluations and services my kids needed. When I wasn't happy with what services were being offered, I wrote a letter to request an IEP meeting to discuss concerns and what would be done to fix this.
I would write a formal letter and mail it certified return receipt and make a formal request for an OT evaluation and any other evaluation you'd like to happen now. If you put in the US mail, it kick starts a time frame and certain legal requirements where they have to contact you with in 10 days, meet with you, do the evaluation & complete the whole process with in 90 days. Making only phone calls and sending emails on the subject does not kick start this legal chain of events and offers them loop holes to get around doing what is really needed.
This is the time to put in all the requests. If you agree to them not doing any evaluations now, it's a process to go back and request evaluations in the future. I had to find a parent advocate to come with me to an IEP meeting after finding and speaking with a disabilities lawyer and had to fight for the additional evaluations after the fact. If they give you any trouble about doing any evaluations now, they will still be singing the same tune about giving you a hard time if you change your mind and want that eval next year. If any part of you thinks he may need an evaluation in any area, do it now. If the school denies any of the evaluations you request or you disagree with their evaluation results, you can file a due process grievance and the district is required to pay for an independent evaluation at a location of your choosing. So while you are always free to do what ever evaluations you'd like outside the district, if money is an issue, have the school either do the evaluation there or have them pay for it. Also to do the evaluations on your own outside the district and not go through the due process procedures, it opens the door for the school to ignore your evaluations, no matter how reputable of a facility you meet with. I found this out after I paid $350 for a learning evaluation & separate psychological eval that the district refused to recognize since I did it on my own dime.
Schools very, very commonly talk parents out of evaluations and services only to save the district money. My aunt is a doctor of special education and said she worked in districts (as in more than 1) where child study teams were told they could only approve a certain number of IEP's & 504's each year and any one beyond that had to be denied no matter what.
The Wrightslaw website has a ton of information but can be tricky to navigate. Most states have a parent advocacy group that you can contact to find out about your legal rights in this whole process, call the state department of education's special education department or a legal aid service in your state (some states have a legal aid office just for disability law). You have a lot of legal rights in all this but school love to act like they hold the all cards when really it's you.
Keep contact in writing, whether by postal mail or email since you can have proof of what was said then but you can't so much with a verbal conversation. If you end up running into someone and they start talking, then follow any conversations up with an email saying "I know we spoke earlier but I just wanted to send a note to review what we'd discussed today" so you have something in writing about what was discussed. You also have the right to record any meetings. It can be helpful when a lot of topics are touched on in a short amount of time.
Most of all, you've got this! It can be overwhelming but you can do this. My oldest is out of high school now but recently said to me that one of the things she learned from me was to stand up for yourself, be polite but don't take crap and don't be afraid to advocate for what you need. Made me realize that all the years of child study team issues not only got her the services she needed but taught her something important about life at the same time. Good luck!!
mom to 3 big kids and 1 toddler!