When your son goes into the assessment with Capita just make sure you have the FOLLOWING questions also ready. I don't know where you live, but I live in London. I also know Capita does PIP (for DWP).
1) What year will his DSA be applied to (this is important with Capita). I say this because my assessor tells me its for 2025/2026 academic year but SFE says its 100% for 2024-2025 academic year as my assessor claims and insist it was for 2025-2026 academic year. But I would believe SFE over Capita so be warned if they tell you its for the next academic year, especially if your sons assessment is now so late etc but it will DEFINITELY be for current academic year (SFE says the dsa for next year isn't even up yet, student loan and maintenance loan is def up for applying now for next academic year for sure).
2) Google the assessor and look for their linkedin. Thats what I did with mine and thats how I knew I needed to complain about my assessor because mine was originally with someone whose been doing it for 5 years then it got switched to a woman who has been doing it for 2 weeks-ish.
3) I don't know what your son has been diagnosed with (and its none of my business) but if your son has eg been getting help from the university mental health team (for example) and Capita tells you that they were advised by eg SFE that they have to have a few companies on the table for it, I would suggest to FIGHT for the university's mental health team (if you son has been getting their help and had a good experience with it). I say this because Capita is doing it by the books (which is understandable) but there will be things the university knows that your son and you may not know and if trying to explain it sometimes yes it may come out wrong but if they university team knows you they'd know you meant no harm but just don't know it and will direct it to relevant teams for certain things etc but if trying to explain how certain things in the university works to someone outside that university they will get it wrong and confuse you and you'd then be playing "chinese whispers" and going back to university and asking to explain and then explaining to the outsider etc (if that makes sense).
4) I know my assessor was weird and I had to fight for a laptop (as well as a few other stuff) as I don't have one and was doing it all my assignments on a phone and I was saying to the assessor can I claim that in September and got told off because she was saying "well how can I justify this for september?". I believe my words to her was "well I failed 2 modules in semester 1 because of my disability and I only have about £150 left of my maintenance loan" I remember her saying well "semester 1 resits are in July EVERY UNIVERSITY has those resit in July". Nope mine has semester 1 (which was september to January) resits in April and I even had to show and proof it to her, which I shouldn't have to do, especially if they were suppose to make it easier for you, whilst July resits are for Semester 2.
The laptops yes you do have to pay the first £200 for it. But the one they give its literally a dell, (as good as Dell is) the one Capita gives, I've seen it, it kinda looks like a ipad pro 12inch but as a laptop (as a tablet its ok but laptop it has rubbish specs) but my assessor did tell me that you can upgrade but you'd have to ask for it when the company contacts you with the list etc
5) Whatever your son needs make sure to tell that assessor to have it for the current academic year (even tho the current academic year is almost over etc) because whatever else he needs for next year its a new budget and you want to maximise all the funding if that makes sense.
6) If you need to know fully how mine went, I've posted a detailed version of it
https://www.thestudentroom.co.uk/showthread.php?t=76005127) It is weird that you and your son wasn't told the 7 day thing and I was. That is weird.
8) If you need help with Capita and if noone else is answering, ask me, I don't mind helping