AAAAHHHH.
A different PHP version...
I changed this "C:\wamp64\bin\php\php8.0.26\php.exe" -f C:\wamp64\www\osTicket\api\cron.php
to this "C:\wamp64\bin\php\php8.1.13\php.exe" -f C:\wamp64\www\osTicket\api\cron.php
And now miraculously it works (duh).
So all that was happening is that the cron job was being called with the old PHP version.
Cheers 🙂