Why won't my rescue dog play with toys?

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

1. 1
   Supplying softer toys
2. 2
   Getting a Kong and putting dog-safe peanut butter or treats inside
3. 3
   Getting down on all fours to demonstrate how to use the toys
4. 4
   Exposing the dog to other dogs who know how to play
5. 5
   Using a different shape entirely such as a small rope toy or a rubber stick
6. 6
   Smearing a tiny bit of peanut butter on the toy
7. 7
   Trying different sizes and textures
8. 8
   Using balls filled with peanut butter or squeaky balls
9. 9
   Using flavoured balls meant for nosework
10. 10
    Using two balls to keep motion high and putting the ball away between sessions

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.