Almost none of what you’ve written is accurate. Hans’s win came in part from a well-prepared opening line (in which he picked up a tiny advantage) and Magnus playing probably his worst (long time controls) endgame in the past 5 years. There wasn’t some single defining move or idea that broke the game wide open — it was a slow, grindy 50 move win where Hans nursed a small advantage and a series of compounded mistakes by Magnus through to a winning endgame.

His optimal/engine-matching play in that game was through the first ~20 moves. Players at the global elite levels regularly have lines prepared through 20 moves. At the 2022 Tata Steel tournament this past December there was a game (Arjun Erigaisi v Nihal Sarin) that featured 40 consecutive moves of engine preparation.

He gave a poor interview after. That’s legitimately been the one real indication that there may have been some foul play in that specific game. But…top level players give interviews with iffy analysis all the time, so I’m not really sure how much weight that should hold.