I think they've sunk every penny they've got into buying the chateau. I think the money is for the costs of the events.
Festivals cost a small fortune to organise, there are so many health and safety issues to consider, so you need public liability insurance, you need venues, stages, sound, lighting. , generators, plumbing, toilets. marquees, medical/first aid, security, permits, road signage, music licence, tents perhaps for the festival goers, glam camping,? actors to play the parts. costumes, merchandising, advertising, waste management, crew, etc. People to clean the site afterwards. Caterers and stalls will pay pitch fees to come of course which will offset some of the cost. If you get event caterers you would pay them to come, but festival caterers pay you.