Ok but picture this: Right after the events of The Cursed Child, they return to the present, but are still in Godric’s Hollow. After such a long time turn, the Timeturner is damaged, leading to an accident of some sort, like an explosion. The blast of said explosion hits Ron, taking him back years and years, to the time Albus Dumbledore was conceived. The explosion also reduces Ron to a simple embryo, which, remaining in Godric’s Hollow, is taken to the closest, safer womb- that being: Kendra Dumbledore. The child grows up Albus Percival Wolfrick Brian Dumbledore, and lives a normal life(a life in which he is gay). Until he reaches the age Ron was when he was lost in time. At the age of 26, he starts having weird visions, flashbacks of someone else’s life(Ronald Weasley). Years pass, and Ronbledore finally recovers all memories of Ron Weasley’s life. He knows no one will believe him, so he keeps that to himself, something he is quite good at. Ronbledore lives his life, being careful not to change anything he remembers from Albus’s life(of which he learned mostly during book 7). He puts up with Tom Riddle becoming Lord Voldemort, and is prudent enough not to change it. This explains why Dumbledore always seems to know everything. It also explains all the odd, and some inept(looking at you Lockhart) Defense Against the Dark Arts teachers Dumbledore hires, because he knows they are essential in the timeline. It also explains how, although sharing many qualities, Dumbledore and Ron are not precisely the same, and have lived different lives; and how Ron and Dumbledore are rarely seen together, among all the arguments of the Ronbledore theory. In The Cursed Child, after coming back from 1981, there is no further mention of Ron. The Timeturner accident might have been left out because it was irrelevant to the plot of the story being told.