Jolly good luck to her - it's a tough sport to be in when you've not got wealth and privilege behind you.
It's a darn shame that the the snob dinosaurs still exist in eventing. It's something I never came across in endurance.
I hope she takes advice before signing into any sponsorship - there was a heartbreaking scenario many years back when a good young rider from South Wales got a sponsorship deal with an office furniture company.
She did extremely well and upgraded her horse....... but the sponsors decided they didn't want to play any more and the deal meant they owned the horse, but he'd rocketed in value and the family sold their home and lived in a caravan so they could buy him back.