Well Caleb that's where MVT comes in to check and see what your users respond well to.

https://www.nngroup.com/articles/multivariate-testing/

Crucially, this approach isn't gonna work in a blanket fashion for every application. There will always need to be tweaks made to the design, iterations, and refinements to best suit the needs, wants, and expectations of its target users.

The short answer here is that if you have even a shred of doubt regarding how well your CTA, or any part of your design for that matter, is performing in terms of accessibility or aesthetic fidelity: bump the contrast and test, test, test.