Okay I found a temporary workaround. I remembered that it crashed when I viewed “multitasking” panel. So I used gsettings to check the keys of org.gnome.ControlCenter
gsettings list-keys org.gnome.ControlCenter
last-panel
show-development-warning
then check
gsettings get org.gnome.ControlCenter last-panel
'multitasking'
this is the problematic panel that was crashing the control center every time. So I did
gsettings reset org.gnome.ControlCenter last-panel
and voila, I can open settings again. Not touching that panel till this gets fixed!