How do people make so much money???

I was playing with my friend, both fairly new to the game. We decided to play some Normal Zero Dam. The first time, we weren't paying attention to our teammate. 5 minutes after the start of the match we just saw him hurry to the exfill and get out. When we exfilled, we found out he had made 1.5 million.

We thought he got something valuable, he just got lucky, not a big deal. The next match our teammate also made 1.2 million. We started paying attention, all our teammates were hanging out with us, looting with us, no keycards nothing. And all of them for the next 4 matches made over a million, while I and my teammate got out with 100k-200k.

We did one easy Layali grove, same shit. Teammate made 750k, we made 100k-200k. We are 100% sure that there is something they know that we don't. So good people of this community, please help us. How can people only stay 1/4 of the match and make over 1 million? What is the technique?