Gonaives has been left under water and cut off from the rest of the country, and thousands are homeless.
The pair toured with a U.N. convoy and Haiti-native Jean told reporters, "It's inhumane. I wish there was a word in the dictionary. No human should be living like this."
Both Jean and Damon are leading campaign to raise more than $100 million (GBP55 million) to help the more than 800,000 Haitians affected by the storms.
Source: WENN