1- I doubt the part about it not having an LCD.
2- It would not be so hard to do the camera with a Monochrome sensor. Some slight changes to the firmware, mostly "Skip the Interpolation".
3- The Sensor manufacturer, used to be Kodak, would do a Monochrome version of the sensor. I called them, they told me so. Some of the same engineers where there 20 years ago when I had them do an Infrared version of the KAF-1600. Probably a run of 50 detectors to make it worth the effort at a minimum.
The advantage- much better resolution (as much as 4x) for monochrome, and twice the sensitivity.My Monochrome/Infrared version of the Kodak DCS200 was an extra $4,000 over the regular $8400 price tag. 20 years ago.
Whether the rumor is true- don't know. Would people buy it? Yes, and it would cost a premium. But, Leica sells out of their limited edition cameras and Leica photographers like to work in black and white.
Oh- and Leica did make a camera that was Digital and also took film. Just a Digital back. My DCS200ir takes film and is also Digital. If I want to use it for color, I load it with film.