Ok this seems really odd to the point where I'm wondering if I'm going crazy.
So yesterday I started a match for Felix. I had intended for him to fight an Alpha Sentinel, probably Steel Will, but he wasn't showing up. I figured "well they might be out of play even though they show up in the gallery" so I picked Zachery. Whatever, change the story up a little.
Today I'm setting up a match with Emily to take on Marshell Percy but now HE'S not available. Strangely though all the Alpha Sentinels ARE available whereas yesterday none of them were.
Is there an issue with Retro character interacting with the match making? I notice Kurio Kaufman is also unavailable for me to have a match with. Unfortunately I don't have another new character to test this out on to compare my available characters for matching.