I don't believe that cross is possible. They are both boas, but from completely different continents. Colombian boas (spelled with an o, not a u) are native to South America. Dumerils are native to the island of Madagascar. They would never meet in the wild. I suppose it may be possible - there are some pretty outrageous hybrids out there - but usually any successful cross is involving animals that are at least possibly capable of breeding in the wild.