Poor Malone, best thing is though that the lumps don`t bother him. I hope, like you, that they heal up and don`t get infected. Hope too that he does eventually `grow into his lips` and not need any ops. Prayers for the ...oops, was going to write little sweetie... but he`s not little anymore is he! Still a sweetie though!

I think that Rilla must feel lonely without Azure and I am sure it would help you both to have another featherfriend.

Unlike popcornbird I was always of the understanding that cockatiels got along with all small birds, budgies (what we call parakeets), finches, caneries and small parrot birds. At one time, after Edge died, I was considering getting a budgie as another companion for Bonnie, never did though only because I don`t think Bonnie wanted or needed one. She was never that interested in Edge really, never seemed to miss her either.
Edge was a cockatiel by the way and I introduced her to Bonnie in the same way you plan to do, although I already had a cage from when I upgraded Bonnie`s to a bigger one. I put the cages side by side for a week or so, for them to get used to each other as much as the health aspect.

Good luck, hope you find just the right little birdie for you both.