They can't use the exact same engine. Firstly, it wasn't near as good as should have been (i.e. better than Grim Fandango). Secondly they would have to write new code for the bike scenes and fights (see press release). Lastly you can't expect anybody to be satisfied with such outdated low poly graphics. While this may not necessarily require re-writing the engine, the outher two points will.
I would prefer mouse control in the case that it's really supposed to be an adventure.