Simple answer is NO !
They are two different speices and have different feed requirements to start with !
I run a guinea pig rescue and bred, showed and judged rabbits for 15 years and i have seen so many injured guinea pigs who suffer badly and its mainly broken backs !
Rabbits love nothing better than having a mad 5 mins and dont care what gets in their way ! Guinea pigs are quite creatures who love eating and cuddling up together in groups.
Food wise, gps make and store no vit c and must have a large amount of fresh fruit and veggies ! Rabbits do not have this trouble and need hard pellets and hay with some vegetables, put a rabbit and a gp in a run, the rabbit thinks whoooopie and runs riot and the gp thinks foooooooooood ! lol
Also gps are prone to mites which rabbits are not but they can transfer them to the rabbits causing problems !
Never keep a gp alone !!! its cruel they love company i have 70 + piggies and not one alone !