Gameplay python files are in "gesource\python\ges\GamePlay", they have the extension .py and are text files so you can open them in a text editor of your choosing.
Opening the desired one and searching "EmitGameplayEvent" will give you the calls that make gameplay events, so search through the desired gameplay file if I don't list everything you need here. You can even add your own if you need to, though this will mark the gameplay as modded on the server list/scoreboard.
Anyway, for CTF the events are:
"ctf_tokendefended" with parameters killedID, victimID, teamDefendedAgainst, weaponUsed
"ctf_tokenpicked" with parameters playerID, teamTokenBelongsTo
"ctf_tokendropped" with parameters playerID, teamTokenBelongsTo
"ctf_tokencapture" with parameters capturerID, teamTokenBelongsTo
"ctf_overtime"
For Arsenal:
"ar_levelsteal" with parameters killerID, victimID
"ar_levelchange" with parameters playerID, level
"ar_completedarsenal" with parameters playerID
YOLT
"yolt_eliminated" with parameters victimID, killerID, weaponClassname
"yolt_lastmanstanding" with parameters playerID, totalPlayerCount
Event names are more or less self-explanatory but if you need any clarification as to how any of them work or under what conditions they fire let me know.