Can’t select customer without administrator user role

It appears that I can only invoice from an account with administrative privilege. This is not ideal, as I am building this for a client that really only needs editor-level privilege. I’m still assessing if this will be the right plugin for me, and this may be a bit of a deal breaker if I can’t figure it out. I assume this problem is because clients get added as any other WP user, and therefor finding them abides by standard WP permissions? Could you let me know if it’s true or if there’s something else that might be going on. Any way to pick from a list instead of the type to generate a match?