Its not really safe to take her outside when RVHD is spreading. Hopefully you’ll be able to get the vaccine eventually, but in many places in the USA, that’s still in the future. Outside time has other hazards as well, unless you have a completely fenced-in garden and no (or very few) birds of pray in your area.

In order to activate your bun, you can start with serving her daily pellets in a treat ball that she can chase around the room. Divide her daily pellets in 2 or more portions and let her work for her food 2 or more times per day. It’s very natural for a bun to have to put in a bit of effort to acquire food. There are small treat balls that are suitable for a bun, but a dog treat ball might work too.

As weird as it sounds, sometimes restricting a bun’s space for part of the day can make them more active the rest of the day. So you could pen her while she normally sleeps, and then during active hours of the day (like morning and evening), open the pen to let her roam around. Usually the bun will run around exploring more when you do this.

I make my buns look for their food by scattering their pellets and veggies around their normal eating area. I used to feed them large chunks of vegetables, but I go through the effort and chopping them up into small cubes or short sticks. They go crazy when they hear the pellet jar or plastic bag shake. The sound of the jar or plastic bag trains them to perk up to me and start looking around for potentially scattered nom noms.

Yes, cat treat balls are quite popular. They also have those forage mats that you can hide food in.