Bloating can occur as a primary or a secondary issue. There may be no other reason ie bullying may not be a factor at all.
I would see whether she feels better after the emeprid and whether her weight then starts to come up.
Perhaps look at her diet also.
Wiebke's Guide to Tummy Trouble
Have you been weighing her daily now?
Have you been able to stop the weight loss with the critical care feeds?
How much weight (in total) has she lost now?
Telling you to ‘get rid’ is awful.
There is a chance with a trio that two piggies get close and then one gets left out. The boar inevitably sides with his favourite and probably the dominant sow.
The two sows will have their own hierarchy and obviously scarlet is the low ranking sow.
Sows can be a bit more subtle in their bullying so it can be a bit harder to spot the signs.
With all that said, trios can work absolutely perfectly and bullying may not be a factor at all in your case.
So, what I would do is wait and see if she feels better after the emeprid and see whether her weight comes back up.
If it does then all is well.
If she doesn’t improve, continue to lose weight then get another vet check done first and foremost - just in case there is then something for the vet to see.
If all medical issues are definitely ruled out and the only thing you are left with is a potential bond issue, then you can do a trial separation. Separate scarlet into her own cage but keep her alongside the other two. If she then is happier, her weight starts to come up and she improves, then you can start to draw the conclusion that she may not be happy being with them. You can then do a neutral territory reintroduction to gauge their reactions to being reunited. If they go back together without issue then their bond was never the problem. If the reintroduction fails then it may be that they then have to live separated side by side permanently.
We can help further with this in time though.
Bonds In Trouble
Keep us posted on how things go
Ps. I have merged all your threads into one. Can I ask that you keep everything to this one thread rather than starting a new post with each update. We ask that it’s one thread for an issue as it helps us advise more easily if all information and background ia in one place