I have a hunch that Kaczyński will gently withdraw and become honorary president for life, a kind of senior statesmen status with consutlative input.
He tried this before with Marcinkiewicz, only to come back when he thought the coast was clear.
Assuming that PiS and Gowin can find any common ground (unlikely, given Gowin's free market beliefs) - the head of Kaczynski would have to fall. For what it's worth, why do you think that people wouldn't stab Kaczynski in the back if it meant tasting power?
Gowin break-away faction of PO, PiS, PSL and Solidary Poland. Maybe also PJN is they meet th threshold.
Except you forget that there is some very real animosity there. Ziobro would have far too many enemies from the PO camp, PJN are dead, etc etc.
If that happened, the PO; SLD and Palikot couild go and f*** themselves.
If. It's not going to happen.
The only certainty right now is that Kaczynski will not be Prime Minister or have any influence whatsoever in the Government post 2015.
What seems quite credible right now is that PiS, after facing yet another disaster in 2015 (despite actually winning the most seats) make a behind the scenes deal to Tusk that can't be refused - they expel Macierewicz et al and accept a genuine power sharing deal that sees real power remain with PO for another 4 years - but in exchange for quite a few ministries. Tusk in return offers some concessions that fits the social agenda of PiS, meaning a win-win deal for most people.
Kaczynski then tries to join Solidarna Polska (themselves humiliated) - but that party is also decimated in the polls, leading Ziobro to join the new-PiS while Kaczynski leads a small minority of lunatics.