I don't know if this will work or not. You can try to get the gasket back in shape by letting it soak in a tub of warm soapy water to make it pliable.
Try Dawn dish washing liquid for the soapy water.
I just had my windshield replaced and before I put the rubber piece on the bottom I wiped the inside and outside with McGuire's Ultimate Black.
If you're worried about it slipping you could put a drop of Permatex Black adhesive sealant RTV in the center and on each corner to hold it.
I just put mine on the windshield and let the cowl push it in place.
By the way, our cars only came with 1 grommet for the wiper arms.
I don't know if this seal fits a Crossfire and you will have to confirm this part is for the lower windshield seal with a Mercedes dealer.
Here's a link to what I found when I searched:
https://mbparts.mbusa.com/oem-parts/...JjaCBSZXN1bHRz