Irresponsible. Quite irresponsible.
It is quite possible that you (or him) NEED to feel ‘un-safe’ or edgy in such scenes. Fine. After all this IS an adult game.
BUT _ Feeling not safe and BEING SAFE are not the same. It is possible to set up such scenes so they can be played out with high safety margin. As it has been pointed out the outcome could have been much worse.
If he COULD have been there and was not – that is absolutely unacceptable.
IF you are having on line relationship he has to find out all details (and you must insist on this) and then he has to plan a scene/task in such a way that you would be safe. And you must contribute – and refuse to do it. In this area it is you who calls the shots.
If he cannot do this – he is not a real Master IMO.
What was his reaction after you were beaten?
I think you need to reconsider this relationship very carefully.