I am actually interested by your theory about how the Dance will happen. Do you think Aegon will “steal” a dragon? How? How will Dany arrive in Westeros? What about Euron/Daario + Victarion plot? Will Daenerys have to kill one of her dragons of “they join” her enemy? How will she understand that Aegon is false?

The stealing of the dragons I don’t think is going to work long-term in either case – I’m pretty sure at this point that Tyrion’s going to ride Viserion, given the bit from his TWOW chapter where he picks up the white cyvasse dragon. Dany’s riding Drogon, natch. And that leaves Jon to ride Rhaegal, named after his father. 

So I’m pretty sure the horn flubs – just like the other magical horn which never brought down the Wall. Moqorro is clearly planning to betray Victarion to his death.

As to how she understands Aegon is false, I think:

1. Prophecy. She knows both from the HOTU and Qaithe that the “mummer’s dragon” is bad news.
2. She’s not going to want to accept Aegon’s offer. She’s the prophesied one with the dragons, and she’s not going to accept being second fiddle to Arianne Martell with someone else sitting the Iron Throne.