If I contribute toward the completion of a dynamic event, but either leave the area or log out of the game before it is finished, will I still get credit in the event that another player completes it? Can I receive my karma in absentia?
Yes, you can. I have had this happen many times, where I'll be walking along and suddenly get rewarded for an event in a previous zone. I have also logged in to find rewards for an event which I was working on before I logged out.