The evidence is pointing towards Solskjaer and the likes of Fergie, Ferdinand and Bruno would only get involved after Solskjaer had made it clear to the board that he wanted Ronaldo.
Below is a excerpt from The Athletic which clearly points to Solskjaer being the one who got the ball rolling as far as the Ronaldo signing is concerned. And once that was established with the board, it was Woodward's role to then sell the idea to Joel Glazer.
Whitwell/Crafton: "Solskjaer placed a call to chief executive Ed Woodward with one aim — he wanted to know if United could do the deal instead. It was a quick conversation. Woodward agreed instantly and set about negotiating with Ronaldo’s Italian club, Juventus."
https://theathletic.com/2794203/202...n-to-manchester-united-how-the-deal-was-done/
Jonathan Northcroft in his 'The Times' column went on to say that Solskjaer ignored the advice of his coaching staff to sign Ronaldo because he believed Ronaldo's goals would make up for his off the ball deficiencies.