I am in an online relationship and we had discussed one day about me getting together to play with another couple on cam.

I liked the idea but I am not going to go out and play with just anyone, I would at least like to know them well enough. I also have reservations about doing that right now, and would like some time to think before I do anything of that nature.
He will of course respect my decision, but he did ask that I at least try to attempt something and see where it goes.

I know two other couples who have expressed an interest in playing and I have also known them both for a few years now.

I approached the Dom of one couple, and asked if there was a possibility that maybe in the near future that I could have a play session with them.

He was only too eager to say yes. I explained that I might like to in the near future and was only asking as my Dom had requested it.

He has since been asking when we could meet. I explained again that it would be later on, and that I would meet them first to chat and have coffee. (I have chatted with them extensively online but have never met them in person).
I have yet to receive an answer to that.

I was speaking to this particular Dom online yesterday and he was pushing for me to meet and play.
I told him that it was my decision and I would decide if I wanted to or not.

I had mentioned in the conversation that I was in the middle of trying to do a punishment, which involved hot peppers.
I am not stupid and am well aware of what they can do. I trust my Dom not to hurt me, and he knows I will not do anything to harm myself.

This Dom started to berate mine, telling me that peppers are extremely dangerous and that I could be seriously hurt. He then went on to state that I shouldn't be with him and that he was closer and could do physically for me what mine can't do.

I explained that if I was to pursue a physical D/s relationship, it would be attempted with this Dom, not him. He still insisted that I need to be with him.

I was a bit pissed about that, he then went on and said that he would do what he wanted in the play session and not what my Dom had wanted in the first place.

I don't know if this Dom is trying to do the peacock thing by showing me how Dominant he can be or if he just thinks that I am going to be fine with just anyone to train me because they are there.

I just wanted to arrange a play session, and that is even if I want one or not.

I could ask the other couple, but they are not into any heavy BDSM sessions, and that was what we were looking for me to try.

Is it even possible to reason with this Dom, or should I just forget the whole thing altogether.

I will discuss this with my Dom eventually, but for now I was just looking to see what I should do or say in this situation. I seem to have a hard time being assertive or saying that this is how it's going to be if it happens and not what you want.