Not debatable at all he used 3 sword style.
He never said 2 swords didn't work and in fishman island when he used the same move the fishmens steel Shields had 1 slice across them not 3.
All 3 swords cutting kaido shows your point is bullshit.
He used three style to create the tornado to counter Kaido's tornado.
The fact there is only one slash makes it debatable, here is the debate and all nonsense aside it is imposible to prove either way:
Your claim: 3 sword base strength + 3 swords worth of ryuo barrier haki to cut Kaido
My claim: 3 sword base strength + 1 swords worth of ryuo barrier haki to cut Kaido
I would lean my way considering Zoro and Kaido are always talking about how Enma is built different and Enma is allowing him to release haki in ways he can't normally.