To get into that part of E21 it's no longer a case of being early, you have to have E21 Forward Accessible Campervan Field accreditation on your windscreen and be on the list. Security to enter this field was very much stepped up in 2023 and it followed in the same way this year.
There is a charging marquee in E21, so a solution perhaps is to get an E21 Quiet Fields Pass and one of the group could take the scooter to be charged after the person who is using it is back at their van? There were a few resales this year of campervan tickets.
There is usually already a waiting list for both Wicket Ground and E21 Forward Accessible Campervan Field before the resale. You will be very lucky in getting a space in either Wicket or E21 unless it is different this year to previous ones. But then again who knows what it will be like with the changes made to the ticket sales process.
If you want to take a chance with a mobility scooter and hire one before the resale, there is a small cancellation fee if you don't get tickets. They took are usually sold out by the resale.
I recently wrote this post about Accessibility which you may find useful. Happy to answer any further questions.
Good luck! 🍀