He's referring to the whole fight as "this sword fight."
He's never mentioned "Who is acting," or "why they are acting."
If just the whole Sword fight "is an act," then that would mean that BOTH Maul and Vizsla were acting.
That's not what he meant. He clearly explained himself saying he was showing Madalorian armor against a force user. So that fight could happen without Pre-Vizsla even having a Lightsaber. He even says in another interview on that fight that he always wanted to see a Boba Fett type guy against a Force user.
Jango Fett has already fought off/stalemated AOTC Kenobi in Movie Canon. Not to mention Kenobi has struggled more than once in TCW against Deathwatch assassins.
Pre-Vizsla having a Saber and Utilizing Amazing Saber skills just makes him an even bigger threat than Boba or Jango Fett.
And let's not forget... Maul still won.