I don’t think he could have made it to the end without winning the last few challenges. His target was also so big that he would have been targeted at around the F6 or F5. Maybe if he kept the more threatening OGs like Reggie, Dave and Estelle around until the F6, then he could have tried to push the narrative that they were all more threatening than him. But some of that was beyond his control (Brenton nominating all 3 of them at once meant that one of them had to go).
I think his flexibility was a good thing. He was perceived as the leader of the OGs, and so would have been targeted by the newbies quite quickly. Making connections with them
And demonstrating an ability to work with them helped counter that. I do think his main weakness was that he went too far with his desire to integrate with the newbies, and so was unable to maintain strong bonds with the OGs alongside building bonds with the newbies. He contributed to Tully’s voting out, which then led to Drew’s demise, while his relationship with Estelle deteriorated throughout their time in the game. This was problematic because Tim needed those people around in the endgame as numbers or shields. Their removal meant that the newbie group became the dominant group in the endgame.
Having said that though, I think the heavy amount of power that is allocated to challenge winners makes it hard to win by just playing well socially and strategically, because challenge outcomes are harder to control. You could be in the top 10 and have alliances with 8 people, but if the one person who you aren’t aligned with wins the challenge, then that could be enough to cook your game. It’s not like in Survivor where you could just build a majority alliance and ride it to the end. In this BB format, a person from the minority alliance could just win a nominations challenge and flip the game on its head. In Survivor, that person can win immunity but then the majority could just move the target to someone else. The problem for the OGs here was that too many of the newbies were top challenge performers, so even if they had stayed strong, it could still have backfired.