Hi
I just installed all the mods and tested it with the expected result. Even when i spawn near or far i can see the silo. sure i have to scroll around the map but it is revealed.
the setting for not reveal the silo also works but remember that map settings have to be set before a game starts these settings can not be changes afterwards!
the setting for the distance of the silo is set in chunks so if you used the default 250 value the silo has to be in a radius of 250*32=8000 tiles from the map center. with the aircraft mod you should be able to find it rather easy.
you could also reveal the map with commands for that area but it will take a while and increases the savefile size