Best solution I can come up with
I disagree and I might be talking crap because I dont keep rabbits but:
You have Dad Rabbit (who must stay entire) and you plan to spend ££ on a hutch and run to let him live in the garden (alone- ie not with rabbits though you have other animals)
You've got MumRabbit and possibly two daughter rabbits indoors.
Mum Rabbit could be pregnant again.
You will need to rabbit proof everything .
Does should be spayed to reduce the risk of uterine cancer anyway.
Bucks should be castrated to reduce antisocial behaviour and spraying.
So in theory you are spending £££ (hutch , run, three spayings + two lots of injections for your new bunnies)
I'd rehome the bunny babies while there's interest.
Spay MumRabbit (reduce her risks and prevent pregnancy)
Buy a huge safe run/hutch so she can live with the male.
Otherwise it seems a bit sad him being outside , them inside , look what you could've won
The adults are your priority, cute as the babies might be. They were here first.
And I'd never put any of my guinea pigs in a hutch of rabbits, guinea pigs can get killed by rabbits (even the RSPCA back that up and the Rescue I got my pigs from prohits the keeping of their pigs with bunnies)