Hello
Adding to this thread because I think it’s the same issue.
It should be easy to recreate this issue in your own environment with these steps.
I’ve put my steps to recreate then the result im getting.
Thanks.
Create 3 simple products
S1, S2, S3
Created a bundle product
B1 is made up of S1 & S2
B1 Product editor: Product data > bundle products > [Add Product} S1, S2
Save
Edit S1 product and add upsells
S1 Product editor: Product data > Linked products [Add Product} B1, S3 to upsells
The result im getting is that on the product page of S1
S3 is showing up as an upsell as expected.
B1 is not showing up as an upsell.