Nevermind, I got a hacky solution similar to the one I implemented in this thread: Question about "Add New Space to Mission Control"
#!/usr/bin/env bash
# Create a new Desktop Space via Mission Control UI (no keystrokes).
# Requires: System Settings → Privacy & Security → Accessibility for your terminal (and launcher, if any).
osascript <<'APPLESCRIPT'
tell application "Mission Control" to launch
delay 0.25
tell application "System Events"
tell list 1 of group 2 of group 1 of group 1 of process "Dock"
set countSpaces to count of buttons
if countSpaces is greater than 1 then
perform action "AXRemoveDesktop" of button countSpaces
end if
end tell
delay 0.6
key code 53 -- # Esc key on US English Keyboard
end tell
APPLESCRIPT
save the script as: close_space.sh and give it execute permissions with
chmod o+rx close_space.sh
then map this command (with absolute path) to a keystroke in BTT and its done.
./close_space.sh
Here is a video of it in action: