You can't play two Charge orders in the same turn. The first one activates ALL previously-unactivated Japanese units
Whoops, that's a mistake I've just been saved from making. Unfortunately Chad couldn't save me from applying the airburst mod for Jungle and forgetting to add the compensating +2 Cover modifer in an earlier scenario
Anyhow here's another thought. If you do enough dieing, you might get a chance to pick a Mortar with smoke off the reinforcement table. Or pick a sighting marker as a reinforcement and wait till it lands across the river.