The bookmakers are strictly business oriented people, if there is a stats that proves Nigeria has big upper hands to win this game, they wouldn't give the 1.9@ odd because if Nigeria wins the match and many people win this game, they will be questioned on their decisions to give Nigeria such odd instead of Nigeria. More over, it can get reduced or increase before that day as they get some hints and information, there could be one player that can change everything about the odd.
Nigeria and Rwanda don't really have much historical data, the ones they have in the last 5 matches held, Rwanda lose a single game, they draw 3 and while Nigeria win one as well. This is a tigh stats in my opinion but what surprises me is that even by ranking, Nigeria isn't there mate, Rwanda is rank 122 and Nigeria is rank 31 place. Unless they are using home game as an advantage here, there is nothing special about them, we shall find out that very day.
Normally African football mostly ends up favouring the home teams. It takes a stronger opponent to go away and get a win. Nigeria is getting more hype to win because the Nigerian fanbase is bigger than that of Rwanda, and the bigger the fanbase, the more hype that will surround the team. But from the table we have seen clearly that Rwanda is a tough side, and for them to be ahead of South Africa and Nigeria in that table mean that those guys are serious. For me Nigeria can't defeat them, especially if they going to play at away. And the Super eagles being in a critical condition needs not to lose this match. I see this match as a potential draw. That's what the Super eagles has been good at lately.