Disabling Wait Room AFTER a Scheduled Recurring Meeting Has Started

I saw some related, but not quite identical, issues with this from other users, so I'm adding a new post. 

We use a recurring meeting in our organization to allow public access and keep the Zoom link consistent. Administratively we have Wait Room forcibly enabled for all meetings as a locked setting. Last night, I was asked at the last minute to disable the waitroom and allow members of the public to join as needed since we were short staffed and someone would not be monitoring the waiting room the whole time. I am a full admin in Zoom and knew I needed to unlock, then disable the waiting room. I did this after stopping the meeting (did a dry run before the actual meeting started). Even after restarting the meeting, the ability of the host to disable the waiting room was still grayed out and the feature was still forcibly enabled. What would I need to do to:

1) turn off one of those administratively locked settings during a meeting (if that is possible)

2) turn off administratively locked settings on a recurring meeting that had already had occurrences and did not yet start for tonight's occurence (if possible)

One angle I did not explore was creating a NEW meeting - because the meeting link had already been published on an agenda, it was not appropriate to change the login at the last minute. I was also thinking that perhaps there was some kind of delay on that toggle to filter through the system, but if there is a delay I don't know what the timeframe would be.

Thank you!