Regardless of anything else to do with WotC, Dungeonscape, etc., I would be completely shocked if this got anywhere near its goal.
Lone Wolf got $170k for their Realm Works Kickstarter. However, this was a publisher that had produced a successful RPG tool before (Hero Lab), so they had a base of people that had already used their products before and would be likely to back them again.
While some people may know Trapdoor from their work on Dungeonscape, they still don’t have a track record when it comes to RPG tools. So if a well-known publisher in the market can only get $170k in funding, I really can’t see Trapdoor getting 2 ½ times that amount.
Still, I guess you never know until you try.