Secret Room in Firing from Vehicles scenario (Bad Omens achievement)

This guide describes the location of the secret room in Firing from Vehicles scenario, part of the Marksmen DLC (free platform update). The room is associated with Bad Omens achievement and obviously with something bigger in the Arma 3 storyline.

Location

The secret room is located in Syrta. It's in the ground floor of the old building located approximately in the center of the town. During my playthrough, FIA off-road was parked outside. Screenshots below.

Screenshots

Big red X marks the spot. Screw you Indiana Jones

The view from outside of the building

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[Cup]

My mistake, it could be ben kerry.....or the brits.....OR its......nope...nevermind

[unsthuthn]

yea Panicsferd has a great idea

[Nicholi]

the plans in the room on the board are the same sizemic maps that you find in the room when you help james recover the device.so it is possible that NATO was completly unaware of this device and the CSAT could have helped the AAF make this weapon ,elading to the british CTRG to look into this sizemic matter detecter

[Panicsferd]

I do not think that this secret room has anything to deal with Cpl. Ben Kerry, via dialogues I think this may be around the same time that the campaign's prologue is set.

Spoilers below (don't read if you haven't played the campaign yet):
I think by going from the prologue with the various dialogues this is I think set around the same time period as the campaign's prologue - what I personally think is that this room could be a safe house for the brits team (captain miller's team - he sounded like he was familiar with the FIA on altis when we were fleeing there) that was searching for that device.

I think it would make since that these brits who are stationed on altis to find that device would have various documents, maps, and even blue prints on this device so that they are able to find where it could be hidden by looking at the recent seismic activity.

[ANGERYkarl™]

Lol i didnt even know about the achievement and i ran in there spraying my MG xD

[Cup]

In other words... Cpl. Ben Kerry TF Aegis.

[Spit facts]

Inside the house there was a map of altis,laptop with the blueprints of the device and some top secret folders on a table also it plays abit creepy music when you enter the room

[Cup]

cool

[Nicholi]

hmmm interesting