For CUDA and CPU mining with your libraries, I added some of the benchmark files for mining photons to a repo here:
Some links in the c++ may be broken as I moved them from a top-level in another copy of the repo.
The above was made by ChatGPT pro, I have not run or verified it myself. I would NOT trust the BCH Secp256 implementation anywhere outside the current application, where it seems to work quite well.
Your issue seems to give a straight-forward proposal for exploring the topic.