I would say that the child is possible but unlikely.
Reasoning: Half-orcs are common. Half-dwarfs are not. In most tolkien-esque universes, dwarves have a problem reproducing among themselves.
So: 1- Just because the dwarf was raped doesn't mean the dwarf was impregnated. 2- If the dwarf is pregnant, it is likely that the offspring will not come to term. 3- Therefore, I'd give the kid a slim chance of survival unless you want to have the Orc/Dwarf hybrid for story reasons.
If it does survive, will it be accepted?
Man, that's a hard one. It really depends on your universe and the culture you've portrayed among the dwarves. This is a fantasy universe, so anything is possible.
Dwarves are cantakerous, hard-headed, and nortoriously unwilling to accept change. In that case, no, the mother and her offspring are outcast.
At the same time, Dwarves are often portrayed with a crusty exterior with warm hearts. You might have a good story situation where the dwarf's family has rejected her but some loan, ancient dwarf with a soft spot for her has taken her in, given her shelter and a place to raise her kid.
What I'd do here is go with here is to consider two things: 1- How has the Dwarf culture been established in my game. I'd want to stay true to that. 2- Given the Dwarf culture, or lack there of, what makes for the most dramatic, interesting story in my game?
Answer that second part, and I think you'll have your answer for your game.