I haven't read his book, but I believe he wanted to combine the 2nd position (communism) and the 3rd position (fascism) to create the 4th position (whatever mold it fits). As well as to unite these forces to fight against the 1st position (liberalism). Dugin dabbled with National Bolshevism and now he's more in-line Eurasianism. Even though he rejects the 3rd position, I think his ideology is Russian 3rd positionism rebranded.
I looked/explored into a bit of fascist ideas (which mainly centers around nationalism, corporatism, and class collaboration - I doubt cooperating with the elites would want what's good for society since they're still seeking to benefit themselves and we're still in the same current mess with we're in due to liberalism + capitalism, 1PT. Fascism historically lent to strengthening capitalism instead. The elites still want to enjoy the benefits at everyone's expense). I also fail to see how this would reconcile or congeal with inceldom because historically fascists believed in social Darwinism and eugenics as well. Assuming all of us are "incels" or other words "subhumans" here, we all want to nut inside of a woman and then leave, passing on our subhuman genes/DNA (our existence and bloodline is predicated on pro-creation, which is literally only purpose of life). Fascism wouldn't allow this because we're assumed to carry bad subhuman genes/dna or whatever. However, I'm not against genetic engineering (if that ever appears in the future).
In terms of communism, that is still very much in the air, sure things maybe more distributed (to render towards a more classless society) but then women will benefit. Some other incels here talk about the idea of "sexual communism." The problem with communism is that it wants to steer more towards an egalitarian society. Anyways, this will depend on however sits on top of the politburo.
I think the fourth position is just mainly the third position rebranded.
I'm for having a strong state (whether it's a form of a Hitlerite or Stalinist state), but sometimes I have qualms about it, in which direction it could go. Sometimes the wrong leader can come in and ruin everything. There's also the risk where it could go the other way; they could bias the state to work more in the favor of foids and cucks instead, which will disbenefit incels. I dabbled with some thoughts about feudalism and slavery (where we could get some sex slaves - in a video game) instead of the state watching over our shoulders saying "this" or "that" is wrong. Since we're black pilled we believe that this world isn't predicated on morals and ethics anyways, we all just want to do our shit in peace.