At least they didn't say it's discontinued. In my recent experience, a lot of MB parts are made-to-order in batches, based on demand. I waited almost 2 months for a trans mount on a 2019 GLS63, and 6 months for a seat module. When the dealer ordered it, there was NO ETA provided whatsoever; just "backordered", and I think in January, they told us it was looking like March availability. And it actually was put into production and became available in March as promised. I'm hoping that's the same for your situation.
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.