Why Did Gregory Kill Cassie in FNAF: Security Breach — Ruin?

In one of the endings for 'FNAF: Security Breach — Ruin,' players watch as Gregory betrays and supposedly kills Cassie during her escape. But why did he do it?

Why Did Gregory Betray Cassie In FNAF Security Ruin?

All Real Collectible Locations In FNAF: Security Breach (Ruin DLC)

Cassie, Five Nights at Freddy's Wiki

bird enthusiast — Not gonna lie, the main ending of fnaf Ruin

How Five Nights at Freddy's: Security Breach is Full of Irony

Any theories on who Cassie is and why she's helping Gregory? : r

Gregory and Cassie's relationship: why the elevator ending is not

10 Best Fan Theories About the FNAF: Security Breach - Ruin DLC

I hope Cassie is still alive after the elevator ending

my theory is that Gregory hadn't actually communicated with Cassie

Roxy worried about cassie - Imgflip

Five Nights at Freddy's Security Breach - RUIN

After the Ruin (MY AU)

FNAF SB Ruin - All Endings Explained; Scooper Ending and More

Did Gregory actually care about Cassie? : r/fivenightsatfreddys