So in the special rules section stated in Mission 2 (tank hunt)
Wagons Move - For each 'Wagons Move' space the Mission Marker advances to or passes, all wagons move 2 hexes each along the road
leading to hex L10 2 and then off the map. Wagons move through and even onto enemy Units or smoke hexes. If a wagon cannot move
because it is 'pinned' or 'stunned' (due to being hit), it instead will attempt to rally. The Player may never take any actions with a wagon, and thus
wagons never check if spent when they move along the road or make a rally attempt.
So does the wagon use infantry hit markers or the vehicle hit markers?
This has to be a typo in the rules, as nowhere does it state that Wagons are Infantry Units. After all, they have a green (wheeled) Movement Cost, which would categorize them as vehicles.
I think the rule should be something like "If a wagon cannot move because it is 'immobilized' or 'stunned' (due to being hit)...". However, Immobilized has "No Rally", so the only way to rally a wagon with an Immobilized hit would be with the Follow Me command card.
I'm guessing it's still up to the player's discretion whether or not they want to use the card on the wagon.
Slightly off-topic: I just realized the AI's Auto-Rally order should also Rally the "No Rally" hits. I think I've played this wrong, where "No Rally" is never Rallied.