I won a round of Junkenstein’s Revenge on normal difficulty. I noticed that “The Summoner” typed a “…GG” at the end of the match, like we had just won a player vs. AI training game.
Additionally, The Summoner got a victory card at the end of the match for number of allies shielded. 
I haven’t seen this pop up in any of my other Junkenstein runs—we melted The Summoner really fast when she spawned in this time (Torb ult + McCree ult + Discord ), I think even before she got to cast her wall, so maybe that threw something off?