How does the queue system probably work for frontlines?

[Sanghelios]

Does anyone know how the queue system probably could work? I just wondering why a friend of mine gets into 4+ frontlines games (Same GC, Same data centre, almost same rank (40/45), same job, same search opions) while i am not getting any queue to pop in the same time. Usually this scenario doesnt happen just once, its basicly always the case. I am already kinda sure, that the system isnt just putting random ppl together. There must be a hidden mechanic wich decides who gets in and who not just like Wolfs Den, where Rank actually matters (Not saying that Rank is a thing is fl tho)

So i do know, that searching for different languages and gc can affect the queue time, but i always wonder why that scenario i have mentioned happen that often.

Edit: If there wouldnt be a hidden mechanic the player who queues first would get in before someone else who starts searching some time later.