Trying to get distinguished hotkeys from two different keyboards

Hi. I have two keyboards, Cynosa Chroma and Huntsman Elite. The huntsman is my main keyboard, and my cynosa is my macro keyboard. However, I want to use OBS to switch scenes using keys from my cynosa, but I can't figure out a way to make a specific key on my cynosa go directly to a hotkey that I could never press otherwise. I was thinking of binding M from my cynosa to something like ctrl-alt-m, but I could accidentally press those keys on my huntsman, and OBS would change scenes when I don't want it to. Thanks for the help in advance!