I believe there are booters in Halo 5.
My connection is spot on good and had a solid 71.96 Mbps.
In addition i reset it every night, for comfort.
I was playing Warzone and this particular player that uses a ghost, killed me.
When i came back with a ghost ultra i killed him.
DIRECTLY after that, i got a huge lag spike, got my ghost hijacked and was kicked from the game.
There was no message in the lobby, it just took me back to the menu.