@SleaterAs much as I love the creativity of the "German" droid, yes, it is rather difficult to read at times because I find myself going over the same lines of dialogue a few times just to understand what I'm reading.
It's fine if your character's accent is supposed to be thick, but you don't have to translate just how thick it is into your dialogue, lol. I'd suggest mixing real words with a few "accented" words just to keep things consistent. Overall though, you want your reader to be able to read what you are writing :)
One thing you could do in the story, is perhaps Fixer finds a voice modulator (or whatever you want to call it) in a pile of parts, has one of the crew install it (or he installs it himself) and it allows him to speak
Basic more clearly. Of course there may be a few words here and there he can't interpret, but for the most part it would be easier to understand.
Anyway, hope that helps :)