Well yes and no. Yes, if they wanted it to be in the canon, it can fit. And yes, things like Umbrella and lickers are connected to the game in a way. However, with plotholes here and there if you tried that (also, you have to believe that there are two [or is it 3 with Resident Evil Zero?] mansions) it works as a standalone as well.
The second one, will be more connected with the game as Jill Valentine is in it (takes place during Nemesis).