Glad to read that Bella Rose is doing better.
I had one experience with Ally, a piggy that I was hoping would be a new companion to Lily. Ally was a food hog and ate all her own veggies as well as a portion of Lily's. She ended up with soft poop like the pictures you posted of Bella's poops. There are a number of threads in this site's archives dealing with this topic, which essentially was to remove all veggies and just feed hay and pellets. Once the poop was normal, you would slowly reintroduce vegetables, one veggie at a time, two days apart. It took me more than 2 weeks to get Ally back on a normal vegetable diet because I reintroduced the veggies too quickly and she went back to the soft poop stage again.
When Ally had her 2nd episode of soft poop, I ended up taking her to the vet and he approved of the slow reintroduction of the veggies. Additionally the vet suggested that I buy organics for the piggies as much as possible. If not buying organics, make sure and rinse the vegetables very thoroughly, due to the pesticides that easily affect the piggy gut.
Just like you, I ended up sleeping on the couch to keep an eye on Ally. In my case, I only have a love seat so it was extremely uncomfortable to sleep on for several nights.