Express shot is a red herring for this, the interaction is with armor piercing rounds proccing on a split shot. A split shot isn't supposed to hit a hero more than once. Armor piercing rounds proc causes split shot to overwrite this restriction and all 5 split shots will hit for full damage...
When selecting "Play Deadlock" and leaving focus from the game (such as through alt+tab or clicking on another monitor), on returning to focus on the game the roster can be exited with ESC and it will skip the previous screen of mode selection and return control directly to the hideout...