I should start by saying that I have fostered with Bunnyjackpot, but I'm responding relating to my own adopting and bonding experience.
My two sows, Mini Roll and Gelato were adopted from Bunnyjackpot Foundation, which was a positive experience. They separately joined my older sow, Misu and neutered boar, Parkin. As Misu, an older lady with health problems, had been extra sleepy. Parkin was so respectful to his lady and was no longer interrupting her sleep, so she didn't think to eat (if we went to wake her up, she'd realise there was tasty hay and start munching). Parkin looked bored. We added in personalities of Parkin and Misu to the adoption application. We adopted Mini Roll in December, who has been a great addition- enjoying zoomies with Parkin, providing additional interaction and interruption for Misu.
Gelato was a foster fail/win, so personality wise, we hoped it was a good match- and piggies have confirmed agreed. Transport wise, she came downstairs for bonding once she was ready for adoption. Mini Roll we collected en route back from a family visit. Bunnyjackpot can and do help with transport arrangements if driving isn't an option.
I bonded both times at home. There was very good support for bonding with a Whatsapp group. The bonding setup is different to what we had when bonding through another rescue. Still a neutral space with plenty of hay, but starting with a smaller grid setup, adding in hideys later the same day, then gradually expanding the CandC grids, before going back to their usual setup.
We have a piggie with medical issues, Misu, who usually drops weight when we go on holiday, or there are other changes to her routine- but during the bond with Gelato- she maintained her weight.
I don't have much else to comment on the bonding- other than to say it went well. All our piggies are happy together and all are benefitting from their different friendships in their herd.
I'm currently not fostering due to personal circumstances, but if there were losses in our current herd, I'd adopt from Bunnyjackpot again.
Good luck to Albert and Bertie!