I am missing some very valuable items from my vault, that were gifted to me through secret Santa a while back.

Is there a way I can see that event log and what items I received, so I can find out what happened to them?

I think I had a green dinosaur minion (I cannot remember it's name, but it was possibly cash shop item), and a few other items.

Thanks for your time.

there's no way for you to check that. If you got them as wrapped gifts via the Arctic Frost you could go back and look. If you got them via your Luminiere Tree you can use URL tricks to go back and look. But if they were just Event Log gifts given directly to your account, no.

You could file a Ticket in Help and staff might be able to help you. Maybe. Not very likely IMO after all this time, but it might be possible.

Did your Secret Santa get revealed to you after gift opening day? Some exchanges work that way. You could just ask them what those items were and then do an Account Search to see where they are.