If I was to guess: this is done.
Working hypothesis: TFC let him stay until Genk are eliminated from Europa League, and they are holed up having a convoluted negotiation over how the price changes as Genk progress. Pozo will need to have Genk pay serious bonuses for advancement, and will need insurance for the injury risk.
Europa League Dates:
Round of 16 - March 7 and 14
Quarterfinals - April 11 and 18
Semi finals - May 2 and May 9
Finals - May 29
I am not sure the Belgium league playoffs can be part of this, other than they may be part of the math of how the transfer fee gets calculated. It's just too complicated, and that would require Pozo committing to 15+ league games until late May (and therefore not arriving until July).
This will be the hard part for Genk - while Genk are in first place, 2019-20 CL and EL qualification are really all about the playoff stage, and those games don't start for 3 weeks. But TFC can say: “we're meeting you halfway, we'll wait for one of your two competitions”, and it's a deal sportsmen can agree to.
There would still be a small chance of his arrival being delayed until summer, if Genk get to Europa League semis, but it's highly unlikely. If they get through, Genk are very likely to be an underdog in the Round of 16 (most of the final 16 teams will be much bigger teams)
If they go out today, he'll be here next week.
—————-
Pure speculation. I know nothing. All I know is, they have spent weeks discussing something, so it must be complex.