Hold on a second. Wasn't Tyrion just reiterating what already happened in previous seasons? That's just redundancy, which is a feature of most mainstream narrative culture and -- like it or lump it -- a crucial part of these long-form binge-worthy series like GoT where the audience is required to remember large amounts of information from episode to episode.
Anyone who was paying attention to Dany's story arc knew basically all that stuff already, and may even have taken some pleasure in hearing the two opposing interpretations of her actions laid bare as they were by Tyrion and Jon Snow.I can see other problems with what they did with Tyrion here, but I don't think a "plot hole" is an accurate way to describe what went wrong.