I would use a Surly 1x1 26" fork with a 29" wheel. Should be no clearance issues since it is designed to clear a 3" tire. You will have to use a disc brake, but no problem since the 1x1 fork has a disc option. The 29er forks are significantly longer than a 26" wheel fork. The ZUM, as I recall, is pre-suspension correction or designed around short travel forks. Adding a longer fork + a taller wheel will make the bike handle horribly in my experience.
commuter turned bike mechanic turned commuter (also a Velocity USA employee, but this is my personal account)