Ken it looks like you tried something to help here. Unfortunately you have a couple of scalar functions in your code and you didn't post the definition of them. BTW, scalar functions are notoriously slow, even worse when you have them nested like you do. 😉

I am certain that we can resolve the problem but without table definitions it is challenging. At best we can guess what the datatypes are. If the OP comes back and posts that there probably be a number of innovative ways to tackle this.