The school can’t just provide you with another child’s medical information, the other parents may not have agreed to that. It may not just be one allergen either. It is very common for DC with allergies to have multiple allergies. There is also the possibility they can’t tell you the allergen because it isn’t yet known. In some cases, it can take a while to find what is responsible.
I just wish they'd also look at his EHCP and see that a child with significant communication issues and eating issues will find their new proposals incompatible with what the EHCP set out to do which was reduce barriers to nutrition.
This may be what the intention is, but unless the other parts of the wording are tighter than what you have listed here, it isn’t explicit what is required. The wording you quoted doesn’t mean what you are hoping it means. The wording you include about toilets also doesn’t prevent DS being in a classroom that doesn’t have toilets within the class. “immediate access to a toilet without needing to request adult intervention” can be provided within other classrooms. You may not think the school will change classrooms now with it being so close to transition but if you push hard when the wording isn’t supported by the EHCP, it is a risk.
I’m not saying they shouldn’t support DS, not at all, but I do think you need to be careful relying on saying the EHCP says X when actually the wording doesn’t.
You are obviously free to accept the visits if you I wish, I was just pointing out you don’t have to and it is acceptable to challenge them even if you were to later stand in court and defend the position.