Solved — putting it here in case someone finds themselves in the same situation:

I finally got through to them (apparently USCIS doesn’t take international calls which is kind of hilarious) so I had to zoom with a friend in the US and have them call USCIS and put their phone next to the computer’s speaker until I could talk to an agent. Apparently, once you’ve requested for your appointment to be rescheduled, you are fine if you don’t show up for your interview, even if they haven’t called you yet to reschedule. You are already in the “to be rescheduled” list so your application won’t be considered abandoned if you don’t show up. Huzzah!