1. They didn't have to rig it. Now that Brendon WAS evicted, they could.
2. They planned on bringing someone back anyway. So they are still one week behind.
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3.Dom/Cassi still had a big fanbase compared to Brendon.
4.Jordan/Jeff fans would've voted for Cassi, who is closer to Shelly who is closer to JeJo.
It still may not be rigged, but I'm saying that your argument doesn't hold water.