Advice on tree with 2 trunks

[dubs_gw]

Hello

I unfortunately have to cut a tree in my garden, but I have noticed that near the base it splits in 2. I would only need to cut the one trunk, leaving the rest of the tree.

I need advice on wheter the tree will survive or not haveing one trunk cut? It is a Elderflower tree, 1 trunk aprx 13inches in diameter (the one I need to cut), the other aprx 9inches.

THe issue is the trunk flares out, which is why the stump itself is not the issue. I'm guessing if this is okay I would get 'new growth' from the stump as well??? These should be able to be routed so not to fale out in furture, right?

Gary