Today I ran across an event called War Memorial. The first stage led me to a point of interest called the War Memorial, which triggered a combat when approached. After the combat, unidentified salvageable items appeared in the site inventory. However, no option to salvage appeared after the battle.
There was an option to investigate the site, but this option just seems to close the window with no effect.
The War Memorial is still there and still shows an inventory including all the loot from the battle and the unknown parts.
Driving the mobile base away and then returning to the memorial once brought up the option to investigate again, but this still had no effect.
Checking my inventory, I do not appear to have received any loot from the battle.
Log screenshot below
Edit: Update! The event seems to have spawned a second War Memorial location which triggered a second battle on the same map, but with different enemies. This battle also had unidentified parts but no option to salvage, and also triggered the investigate dialog shortly after, which revealed a third War Memorial following the same steps. The event appears to be stuck in a loop that prevents looting and salvaging and resets to the point where a War Memorial spawns.