The penultimate episode of Star Wars: The Clone Wars featured Order 66 going down, albeit from a different point of view. We finally got to see how Rex and Ahsoka Tano handled the tragedy, and they both survived thanks to the actions of another clone trooper, done in a previous season.
It's not a big surprise to find out that the actions performed by ARC Trooper 5555 (aka Fives) in the first arc of Season 6 played a big part in how this duo of favorites escaped their betrayal-by-blaster. Rex manages to hold off on gunning down Ahsoka just long enough to spout out Fives' name, and that leads Ahsoka to looking into the records of exactly what Fives discovered before he was killed.
She doesn't have the luxury of watching all four of those episodes (Republic cruisers don't get streaming services, but she does get the "official" report as well as a grievance report from Rex himself. Rex was close to figuring out what Fives knew, and soon enough Ahsoka knows the truth about the implants within the clones that trigger Order 66. It's not long before she has Rex is a space CAT-scan machine, and his implant is being ripped out.
Sure, we knew that both of them survived because they both show up in Star Wars Rebels. We also knew that the discovery by Fives was likely pivotal — it's just nice that the series went all in on connecting the former arc, and the legacy of one of Domino Squad's very finest.
ARC Trooper Fives may have died in Season 6, but thanks to his actions there, both Ahsoka and Rex survive Season 7. Our heroes over at Jabba the Pod (Brian, Caitlin, and Matt) break down every implant and order contained within the penultimate episode ("Shattered") in their video series, which can be seen below. "Good soldiers follow orders!"