Grouped Product Configuration

In the linked page I have grouped a simple product with a variable subscription product and it works.

Now I have another product with a “designation of funds” (drop-down) to different donation accounts, here – https://aboki.org/36931-2/

I would like to add the same variables to the first page/product so that there would be the designation drop-down in addition to the payment buttons. I tried to add the variable product to the grouped product and it didn’t work.

I see in your demo 3 exactly what I’m trying to build. Perhaps my approach is wrong. Any direction you provide would be appreciated if my request is feasible.

Thanks again for a great plugin. 5 stars.
Stuart

The page I need help with: [log in to see the link]