[2x2 Tournament] Double Up [SoD]

So what? And Kreg used a level 5 scroll – Sacrifice – in a battle against Scorpio. And what was he supposed to do? Use level 5, but not level 4? Or build 2 Castles? That's complete nonsense.

yes, exactly – it's nonsense
formally, the conditions of the rules for Sacrifice were met
but for Teleport, they weren't; level 4 was possible, but they built something else
true, for Sacrifice, 2 Towers were built anyway, but for Teleport, 1 would have been enough, just in the right place)
and for both scrolls, with the current wording of the rules and a similar arrangement of Castles, they should have built 1 Barbarian and 1 Castle – then there would be no grounds for criticism (for those who freely interpret the concepts of "own" and "enemy" Castle, there is an argument – heroes can also learn spells from an ally, which means that all Castles are their own in terms of Towers))