Slitherine

The 1-strength British commando unit was initially hidden.
The selected Zündapp tried to move onto the location and revealed the commando.
I think units should only reveal hidden units it they are able to move to a location next to the hidden unit.
In this case, the Zündapp should receive some fire, but the commando stays hidden.

Anyone guess what the scenario is about?

This issue is similar with mines or submarines when units are going to travel through other own units and the target hex is blocked by a hidden unit. There is combat and damage but the traveller is still far away stopped.

DLC '42/43 West? St Nazaire, Operation Chariot?

Correct, a cookie for you.
I've just started work on that campaign. We'll see how far I get before I run out of unit types.