There's no way he will play for us before the next window unless he's released by his club.
FIFA would never allow this, otherwise many will use it as a precedent to get around the deadline when they need to e.g. De Gea's failed transfer to Real Madrid.
What I'm more interested in is a proper explanation of exactly what happened here, and who is mainly at fault. The hypothetical scenarios, assumptions, and crazed blaming going on around here is ridiculous.