I know quite a few people on InterNations use this site as an alternative to Airbnb. Before your next booking you may want to be aware of WIMDU’s supposed "guaranteed satisfaction" policy. In the case of problems with accommodation, this company does not accept any responsibility!
A. They have a no-refund policy - if you are not satisfied with the standard of accommodation, it is up to you to arrange a refund with your host
B. If they choose not to respond to your emails there is nothing you can do and no way you can contact them. There is no emergency hotline you can call if you are truly desperate.
NB. Interestingly enough, if you have a negative experience, you are not given the opportunity to “rate” your experience on the site.