I'm almost certain that paying out LvG's contract has little to do with why he's still in charge; I can't imagine many people actually think we will actually get top 4 now and everything they do now must surely be in preparation for next season.
I suspect that either the board or Mourinho himself do not want to take over until either the end of the season or it's at a point that Jose can't be expected to achieve anything, as if he were to come in now some people would still expect him to achieve a CL spot.
Either that or Woodward is so genuinely incompetent that he's now aimlessly chasing Pochettino instead of just appointing someone who could actually make the team competitive again and has the personality and clout to bring in players despite having no CL football.
Have to admit that while I still don't really want him as our manager, one of his biggest flaw matters little currently as it's not like LvG has been that good for our youth system either, most of the u18/21 players we've called up have been down to pure necessity rather than their actual quality, or he's gone with midfielders playing out of position while he ships out actual talented young players (Welbeck, Thorpe, Keane etc)