in fact, spouses of Ukrainian nationals should be allowed to join them in Germany BUT you would have to prove that you resided in Ukraine on 24 February 2022.
As your case is more complicated, it's a good idea for your wife to inquire at the Ausländerbehörde in Chemnitz. Düsseldorfer Platz 1; 09111 Chemnitz; Maybe calling would work too: +49 371 488 3371
They will be able to tell you what you need (international marriage certificate etc.)
Wishing you all the best,