Bill Randa does not die in Monarch: Legacy of Monsters itself; the series shows him alive in the past. His death happens in Kong: Skull Island , where he is killed by a Skullcrawler on Skull Island.

What happens

Bill is part of Monarch’s Skull Island expedition, and after the mission goes wrong, he gets attacked and eaten by a Skullcrawler. Some retellings describe the moment a little differently in creature detail, but the core point is the same: he dies on Skull Island during the expedition.

In the show

Monarch: Legacy of Monsters uses flashbacks to show Bill before that death, which is why he appears in the series even though he is canonically dead by the time of the main present-day story.