I missed part of your question about playing a Mollenhauer in and some oiling tips. They have an aptly named “Worth Knowing” webpage at:
https://www.mollenhauer.com/en/worth-knowing#content
I couldn’t find anything about Mollenhauers being wax impregnated. If they’re not, an oiling regimen is a good idea. I oil my Mollenhauer Denner Treble and feel that oiling of its labium does something very nice to the instrument’s voice. I did find that the outside has an oil finish. That said, I’m going to start an every-now-and-then light wipe down that will also keep it clean and new looking. Enjoy your new recorder… — k