I've only just seen this ( the perils of a technophobe having tapatalk - I've not worked out how to see the folders yet, so i only get notified of the posts I've commented on)
If it is laminitis, regardless of the reason it's happened the basic treatment is pretty much the same - the vet is the only person who can advise and give any medicines for it, although you're never going to go far wrong with an incredibly deep bed right up to the door and regular small amounts of well soaked hay.
Nobody can possibly say what is going on inside a foot (until the changes are big) without X-rays. They are always a good idea anyway, because without them you don't know where anything is to be able to trim and shoe the hoof to help the horse. Heart bars ( be they plastic or metal) need precise placement to do their job - it's not a case of just slapping them on and hoping for the best. A good vet and a good farrier are your best friends in this kind of case, they work together for the good of the horse.
The other thing that X-rays can help with us when he can come off box rest - until his feet settle down and things are stable inside he really shouldn't be walking about, the laminae are still breaking down and if he does too much he can do a lot of damage.
You can nurse them back from rotated pedal bones, but it's not nice for anyone, it's expensive, it takes a long time and it's a lot of work - and that's before you get into the ( IMO more important) moral dilemma of "is it fair/is it kind" again - imprint shoes ( the plastic ones) are fantastic to help and Andy Pointon is a genius, but they are expensive and if the horse isn't insured for whatever reason then that can be very prohibitive. ( she should really sort that out if he comes through though - TBs are notoriously good at injuring themselves, it's not true that it's hard to insure them unless there's something she's not told you!)
It might be worth contacting the RSPCA - they do occasionally help people out with big bills ( it might be better for the vet to ring them though, the vet will carry a bit more weight on the phone than a concerned friend) although your friend will then run the risk of possibly being told to sign him over to them. ( they don't always) I'm not sure if World Horse Welfare have a fund to help the public with vets fees, they may well do, it's certainly worth asking - worst that will happen is that you are in the same situation as now. The blue cross don't do horses i'm pretty sure, but even if they did you have to fit their criteria, which are quite strict.
The weight loss is almost certainly ulcer related - there are treatments which vary in price (!) and effectiveness, but it's probably less pressing for him right now than helping his feet, we can deal with that later
IMO - the first thing to do is find a couple of hundred pounds (or negotiate a payment plan with the vet - 90% of them aren't unreasonable!) and get his feet X-rayed. At least then she will know what she's dealing with and where to go from there.
Shout if I can help - I'll have a think and see if I can come up with any other ideas to help with the money side of things... Good luck