Election worker here.
Election clerks have no way to check citizenship. That must be done when the individual registers to vote. It is the job of the state to keep the voter rolls free of corruption. All election personnel can do is verify identity and that the individual is on the verified voter roll.
Of course anyone openly admitting that they're not a citizen would be reported. The Project Veritas videos highlighted gross negligence on the part of the election workers, apparently in a sketchy polling place.
The problem is that this is likely going on quietly all over the state, and there is no way for election workers to tell an eligible citizen from an illegal as long as they are on the voter roll.
Needs to be addressed by the state. I hope Abbott follows through, and he probably will. .