A fair point. I guess Olusanya is proven chaos, whereas those two are unproven chaos! Olusanya has the physique (height, basically) that Keskinen lacks against big centre halves, and Bilalovic seems to be quite weak and lacks the diligence to even do the forward role. Bilalovic looks like the type that has the potential to be good, but will probably never fulfil it. Unless he has an amazing preseason, I'd like to see him go somewhere in Scotland on loan for six months to sharpen him up and get him putting the work in.
What's most frustrating about the Olusanya situation is that he, and none of the other options, are actually as good as Esther Sokler. With a bit of work, he could have been a great asset when playing two up front.