Sorry no-one has answered sooner. This is not an area I have any experience of, but the following was was some advice Stef gave to someone else on the forum with a 325g hoglet and a smaller one (hope you don’t mind me copying this here, Stef):
You need to contact a local carer and get it checked over. Once this is done pretty much all carers will be happy to return it to you for overwintering.
Most juveniles picked up at this time of year have internal parasites. While these are not necessarily dangerous in a hog in a normal environment, when they are in a stressful situation – ie in captivity, they are known to get considerably worse and can easily end up causing the hog to die. So while my advice may seem extreme on what seems a healthy hog, it’s really worth doing. The BHPS number on this site will be able to let you know of any carers in your area.
They will also be able to give you lots of advice and be a point of contact if anything starts to go wrong.”
“You need to weigh it now. Then again in a week – assuming it eats everything every night. If there is any weight loss or poor gain then it will need checking for internal parasites.
You can take a poo sample to your local vets and ask them if they can check or alternatively send it to Vale wildlife hospital and they will check it for you. They do charge for this
“With regard to exercise the only thing to do is give them the biggest cage you can. It is not ideal but it’s better than being in the wild unable to cope.
Hogs do not take to exercise wheels or anything. You will need to adjust their diet accordingly as time goes on so that they don’t get fat.
In a large cage you can also scatter the food so they have to forage for it rather than just eat from a bowl – but this doesn’t work in a small area as it’ll end up being poo’d on
I have found a lot of the hogs I’ve overwintered will naturally regulate their intake but that’s over hundreds of hogs and not the 3 you have, some are quite happy to just get fat!
Keeping them together also helps as they will be more lively but do make sure one isn’t being bullied so you will need to keep weighing regularly”
Also the following is a link to a site about looking after hoglets.
Sorry this is not advice tailored specifically for your circumstances, but the best I can do with my limited knowledge.
Good luck. I hope the little hoglet is still ok.