Problem is that failing to communicate will lead to huge productivity holes, so to "fix it", either the natives need to learn a non native language or the incoming immigrants need to learn the native language..

So, attracting the international workforce to come Germany vs being able to fully utilise them are completely different ballparks..

This is Germany we're talking about, right? Something like half the population already speaks English to some degree and that is specifically concentrated in the part of the country that is already highly educated and would be working with those immigrants.