Key sequence for Escape stopped working

I have a key sequence set up so that pressing and releasing the control key (which I have swapped with my caps lock key in System Preferences) sends Escape. This used to work system wide, but no longer does. It works in Terminal, but not iTerm and not Slack. I can work around it by enabling the "HUD Overlay". Of course this is fairly obtrusive. Is there another way I can fix? Thanks!

Device information:
MacBook Pro, 15-inch, 2019
MacOS 10.15.2
BetterTouchTool 3.330 (updated to Alpha before submitting bug)