I don't know Tony at all, and in theory I do support a person's right to end their life if they wish. However, if I were in the channel at the time, I would do

I don't know Tony at all, and in theory I do support a person's right to end their life if they wish. However, if I were in the channel at the time, I would do exactly what the channel participants did - immediately try to contact Tony, people close to him (or anyone that might know him), and the authorities. Somehow there is a distinct difference between philosophising about the right to suicide, and a very real, specific case of a fellow human being in distress. I don't know why I feel this way, but I have a very deep feeling that this is the right thing to do.