Just finished Taen Quest and got Zekrom and Reshiram, went to where Kyurem spawns in 2nd ice puzzle. Got to the little island and he isn’t there. Halp
Are Zekrom and Reshiram on your team when you go. I haven’t gotten there yet but it might help.
It is not obtainable on 1.2.3 due to a bug. It is only accessible through the Discord test patch.