I’m having a similar problem. I show “Media Offline” in one of my sequences – the one where I have done all my edits. But in other sequences of the same project the media is visible and connected. When I go in to reconnect the media, it is found and goes thru the process of reconnecting but remains… unconnected. I can bring the same media into the sequences and it’s visible but all my work from before is worthless.
I am working on it now… will post again if I can figure something out. It’s really frustrating though!