Breaks ajax functionality on simple products

Highlighted in several posts, it appears that this product does indeed add ajax functionality for variable products, however, in doing so it breaks the ajax functionality on simple products.

I have tried with our custom theme, I have also tried with default WordPress templates, such as Twenty Nineteen, every possible scenario results in the same thing, it working for one but not the other.

Would the developer consider highlighting this as a limitation with the plugin, or provide a solution, I’m just seeing closed threads to this issues and no solution.

Thanks