Thank you so much to both Pepe Le Mokko and Fotis1991! Ultimately, I find Fotis1991's solution to be the most robust for my purposes here. This is very powerful, and using this function, along with a bunch of others I've been piecing together, coupled with a couple hundred hours of my labour, Excel will be able to solve serious problems and feature requests that our database software company hasn't been able to solve in over ten years, as well as likely hundreds of hours per labour annually, and have lots of fun too!

Thanks again to both of you!