Right now there are four possible scenarios for CSKA, two selling ones, and two non-selling ones. I'm assuming some percentages so bear with me. Also assuming the final Milan offer is 3.5mm, the bonus for getting out of the group stage to be 3.5mm, and 1mm for each win in the group.
Scenario 1: Honda is sold, they qualify anyway (10%), with 5% chance to leave the group, 95% to get knocked out in group
Scenario 2: Honda is sold, they don't qualify (90%?)
Scenario 3: Honda not sold, they qualify (80%?), with 75% chance to leave the group, 25% to get knocked out in group
Scenario 4: Honda not sold, they don't qualify (20%?)
Furthermore I'll assume that they have a 5% chance of making it out of the group w/o Honda and 75% w/ Honda (of course that'll depend on the draw). To be conservative in this calculation, I'm assuming that if they don't make it out of the group, they get at least one win (against the group whipping boy) when they sell Honda and two when they don't, good for 1mm and 2mm respectively.
Also, there's a wage savings by selling Honda earlier of half a season (50% of 2mm Euro, or 1mm) in addition to our 3.5 million.
The expected value of selling Honda is 4.63mm and the expected value of not selling is 3.30mm after putting that into Excel.
And there is also the added bonus of having an extra half season to get Honda's eventual replacement in sync with the team as well as not having an unmotivated player who will be leaving soon guaranteed on the team.
Even if the expected values were the same---there's less risk selling Honda now, so in conclusion CSKA SHOULD SELL US HONDA!!