Still doesn't work. I guess sprites don't allow touching for some reason.
It's easy to work around at least, but it uses twice as many entities, which kind of sucks.
I make a second entity with no model, basically just a size and a SOLID_TRIGGER, and I save the sprite's entid inside the EV_INT_team value so I can delete them both later by just referencing the "active" ent.
As far as the sprites are concerned, I had the sprite created with SOLID_BBOX for testing purposes, and I could dance on it and touch it and everything, but as soon as I spawned it (started the animation), it was no longer solid or touchable.