I would be very cautious when buying tickets or even glamping offers on eBay. There are many scams. If you do buy, only do so with buyer protection or via personal pickup.
Please note: Third-party ticket resale is not permitted, or rather, you should ideally use the official ticket exchange. However, this usually works poorly, and as current sales figures show, there probably won't be a ticket exchange at all this year. I'm not sure if it's possible to transfer glamping offers yet.
Long story short: Be careful.