I'm really sorry for your loss. I think the flower essences is a GREAT idea.
I also think 2 months is too soon and maybe eventually a companion would be a good idea (it all depends on each case) but it's still too soon for all of you and would just probably stress Mitza (plus what you were saying about the dog)
As well as L4H I don't think he should go out either.
I'm also sad to hear about Kitty and her struggle. Mom2Kitty be strong for your furbaby