There have been past episodes of ballot shenanigans in Houston from the wards of Sheila Jackson Lee and Eddie Bernice Johnson. I’m guessing there were just more of it this time, partly from Beto supporters and partly from illegals.
A few years back there was to be a large and serious case dealing with voter fraud. So the day before the trial was to begin the building with all the evidence and all the voting machines is burned to the ground. 10,000 voting machines.
Found some article:
https://www.nytimes.com/2010/09/11/us/politics/11voting.html