I believe so, I was at his promotors last event in Mid-March, he was supposed to be joint headlining but the fight was called off at late notice.
Its strange to me why we don't have more foreigners boxing out of the UK. Whoever promotes Yassine has been doing well with him and Spencer Fearons cards are always sold out with a mega atmosphere so it can be done, its just not on TV. Germanys boxing scene is pretty much run by Ukrainians, Armenians and Bosnians.
Germany is right next door to Eastern Europe, and has had a decent number of immigrants in the country for a while. A lot of boxers are sons of immigrants: Abraham's parents moved to Germany when he was 14, Sturm was born in Germany from Bosnian parents, Huck fled Serbia in the early '90s etc... I don't think importing foreign boxers would be all that interesting for British promotors as building a fanbase will be hard and they can't fight for the titles Sky thinks are important: the British, Commonwealth & European. El Maachi has had a very tough time getting opponents because he can't get ranked anywhere. He beat the EBU #4 last time out, it didn't help him one bit. German television doesn't really care for titles other than the "world" titles from the WBA, WBC, WBO & IBF, so it doesn't matter much if the fighters aren't eligible for regional honours.