Hope you are well Please see attached In the first video, am

So in video 1, the parked cars and obstructions are on their side. They seek to have passed the cars and given them a wide berth which is recommended in case of car doors being opened.

You didn't need to stop unless it was obvious there was not enough room for you and the cyclist - also the road seems wide enough for the parked cars, the cyclist and your car so no, you would not be expected to stop. There was no parked vehicles on your side either. Generally if the obstruction is on their side, they should have slowed or even stopped but he just flies downhill it seeks.

The second video is the rear facing camera and the silver 4x4 behind you. The other car comes close to you as you negotiate the roundabout. The final video is the forward facing one and it looks like both you and the other car set off around the same time to turn - they are indicating right before they approach the junction. I think if you left it any longer it wouldn't be good as they would have already been across the roundabout / committed to their turn and they would have had to have stopped to let you cross. Both you and the other car are moving through and neither has to break so it looks fine to me.