fortune favours the brave interaction

How does fortune favours the brave interacts with items that force content?
For example if i put expedition scarab in map device can fortune favours the brave roll expedition, if yes does it mean i just wasted a scarab or is it not used in that situation.

It gives you a random Kirac League Mod. Sextants and Scarabs should act as if you had selected the applicable mod on the map device. Note that Scarabs read "contains an additional." You would end up getting 2 expeditions in the map and both would benefit from the sextant modifiers.