When you're watching Charles, you can see "endMission", "startMissionEvent", "endMissionReward" and all that kind of stuff.

Use a distress call, watch Charles, (sequence) and see what the response says about using a distress call.

Next is to create a rewrite rule to modify it. I'm certain this will result in a CVE or an unsaved state on refresh, but it's fun to mess around.

In Rewrite Settings, click Add, name it something.

In Locations( in the upper right) , click Add, only fill in Host "n7-maa-app-prod-active-vip.playdom.com"

Under Rules click Add, Type: Body, Match Value:   "useDistressCall" (just guessing here)
Replace Value: "useDistressCall,useDistressCall,useDistressCall,useDistressCall"

see what happens, mess around more.

I can't get anything to happen here after messing around with a bunch of stuff.

You might could look up distresscall in ce.swf