Hello @Joe Fowler ,
Thank you for posting here.
1-Are some of your devices you mentioned non-Windows devices?
2-Is your Windows CA configured with SHA 256 or SHA 384?
If your Windows CA is not configured with SHA 384, you can configure your Windows CA with SHA 384 and set up Windows OCSP in your lab to see if it helps.
Public Key Infrastructure Part 8 – OCSP responder
Q: Is there a configuration or minimum baseline for this to be supported or is there a registry hack or is this something that currently isn't supported by the product?
A: I am sorry, after my research and my knowledge, I cannot find such reference or any information about it.
Hope the information above is helpful to you.
Should you have any question or concern, please feel free to let us know.
Please note: Information posted in the given link is hosted by a third party. Microsoft does not guarantee the accuracy and effectiveness of information.
If the Answer is helpful, please click "Accept Answer" and upvote it.