The Kaminoans are so dodgy that I just can't believe that anyone took Lama Su's statement that Sifo-Dyas ordered the clone army seriously.
Ah yes, the unethical, corrupt, slaving, murdering, Sith-serving Prime Minister of Kamino is most surely a reliable source of information.
All that main canon says is that Sifo-Dyas was friends with Dooku, had visions and foresaw the need for an army, which he campaigned for. That he actually contacted the Kaminoans and ordered the clone army is 100% retroactive stuff from the EU/Legends written post Episode 2, or claimed by lying Kaminoans and equally lying Sith Lords.
It would make far more sense and be a far smarter plan to not bring a Jedi Master who can see the future into your evil Sith plans. But it would be very convenient if a Jedi Master who previously tried to encourage formation of an army had his name associated with the surprise clone army when the Jedi finally find them. And if he's missing or dead, he can't be asked about it.
Dooku did everything else. He recruited Jango, he concealed Kamino, he's the guy the Kaminoans contacted when things went wrong. All he had to do was say "Hey, when the Jedi ask who ordered these clones, say it was Sifo-Dyas." Maybe he even went to the trouble of making [email protected] and pretending to be him for a bit. But honestly, why bother? The Kaminoans clearly do not use Know Your Customer (or care).
Dooku claimed in TCW that Sifo-Dyas "helped him". But Dooku also killed the guy. It's not a stretch for the bad guy to reframe his killing of his own friend as that friend helping him. Sidious would have loved making Dooku kill his friend to prove his loyalty and destroy his ties to the Jedi, that's right up his alley.
