Yes, Webnode is a legit company. They have been in business since 2008. Originally, they are a Czech company, which is also where they still have all their development and operations. The headquarters are in Zurich, Switzerland. From our own experience, we can tell that Webnode honors their money-back guarantee.
It can always happen that scammers build a website with Webnode, but these get usually shut down quickly by the spam team.