No, no Shimano XDR hub since XD/XDR was invented by SRAM.

The Alfine 11 hub was improved by Shimano a couple of years ago to make it stronger and compatible with Shimano Steps and other pedal assist motor (it wasn't before) which opens a huge market for it (previously, only Nexus and Alfine 8 were usable for ebike) but strange enough, there are still few ebike with Alfine 11 while there are more with the much more expensive Rohloff or the similarly priced Enviolo hub (even if this one has a very bad efficiency and is much heavier).

Also, nor Riese & Müller nor Pacific Cycles propose a Birdy with Alfine 11 while they have one with Nexus 8 and Rohloff, again I don't know why because from the specifications and price, the Alfine 11 should be a good alternative (better also than the Pacific Cycles 3x8s with Sturmey Archer hub) ?

The dual drive doesn't exist anymore and even spare parts aren't available anymore. There is similar system from Sturmey Archer (Sunrace owned) mounted by Pacific Cycles but its heavy and has a lower efficiency too.

One last point, besides the potential reliability issues of the Sunrace hub, the solution of R&M work very well and gives a good gear inch and range. I rode my Birdy Touring during a little more than one year with it mainly loaded without any problem and doing many km with it, besides normal wearing, there was no mandatory need to change it.

I also cannot imagine that R&M would keep the Sunrace solution if there were a lot of failure with it.

Glye, when you had this problem with the hub, did you contact R&M directly or with your R&M dealer, did you receive any feedback from R&M, did R&M took the problem under warranty ?