I saw a few Royal Guards at a small, middle of nowhere WM and grabbed some. Never saw Lando or Ackbar. Saw Jyn, Death Troopers, and Ahsoka twice. Cassian once. Scarif Trooper never.
Heck, poor Jesse went out of his way to grab Han/Leia/Phasma for me because they never showed up here, then they show up everywhere for $6 literally two weeks later.