If you have a google G Suit account for educational use and are able to create your own Google Meet rooms, you are able add (call) any US/Canadian +1 number free of charge. The number of which is observed by the scammers is different each and every call, which means you are able to call them right up again–even if they block your number.
However be aware that I am not sure if--or what logs are kept regarding the usage of this system in google's side of things. Not sure whether the organizor (school/college/university) of the GSuite account is able to see what numbers you call through the google meet.