Can Buddhism be fundamentalist?
Let's put it this way - a Buddhist is a person who has taken refuge to the three jewels, follows and walks the path taught by the Buddha. Those who do not, are obviously not Buddhists already, rendering your question un-applicable.

Having said that, Buddhist respect other traditions as long as they do not violate the five precepts, and acknowledges that if other paths do not end "true-suffering", then they are not to be pursued.