No, it wouldn't have been a hit even if it was sold with an amiibo or two. The game was so not kirby (although the visuals and the artstyle are so lovely!).
I'm also reading a lot of people saying they will buy the chibi robo game just for the amiibo.
I'd say wait and see, because how many are going to buy the game just for the amiibo? I don't see a million of people buying the game only for that!
I think it will sell moderately, with the amiibo, those recent interviews saying that if the game sells badly it may be the end of the franchise (I'm sure that would drive some sales) and also well, the game looks cute and fun!
If the game ends up selling let's say 1 million worldwide just because of the amiibo, put an amiibo in everything Nintendo xD
Ps: I'm buying the game, probably without the amiibo. It's only 22€ in amazon spain. Can't say no to that price!