Is there no way to dismiss a timer/alarm with the earpod controls on iPhone that does not result in resuming playback?
What I do to stop alarm sound is to call Siri twice. First time to stop the alarm itself, second time to stop Siri from listening. This can be done with a very short interval. For reassurance, you can tap thrice each time (in case you tend to miss one of 2 taps required for the command to be registered by AirPods). 

P.S. I know the question is about EarPods, but it's quite similar to what some people experience with AirPods. And for EarPods the same could be performed by double-clicking the central button.