Just seems like bad reporting by Morosi. Rosenthal said he heard from a "credible" source that Ohtani was going to TOR. He dug a little deeper and found out it wasnt true. I imagine that info was passed around to other insiders, Morosi and that Dodgers writer too.
Morosi gets the tidbit, tweets out a decision is "imminent", probably believing that its the Jays based on his source but isnt 100% sure yet, so he doesnt say the team.
The LA writer see's this tweet from Morosi and starts believing the info they recieved is real and decides he'll drop the bomb.
Then someone feeds Morosi some false info about the plane heading to Toronto. Morosi himself says CAA did not confirm if Ohtani was on the plane, but he probably thinks they dont want to leak it, so he puts two and two together and drops the bomb that Ohtani was on his way to Toronto. Neither of his scoops were true, he failed to verify either of them and still reported it.