Hey'a, been running a lot of Magister's Terrace recently on Classic Cataclysm and noticed that Rarity doesnt track attempts of getting Swift White Hawkstrider. No idea if it's related to it, but i noticed in config there's no Kill Statistic ID being set.
Thanks in the advance!

From some testing done, there's some additional stuff:

• Kill Stat ID isnt at issue here, adding it doesnt matter as the kill stat id refers to both normal and heroic kills
• Checking instance with GetInstanceInfo() returns that Magister's Terrace returns Difficutly ID 174 instead of 2
• Checking all instances from LFG/RDF returns that all heroic instances have Difficulty ID 2
• Difficulty ID 174 (and 173) are Classic specific.
• This ID appears when I ran in to the instance, joining by LFR/RDF not yet tested
• Running into Auchidaun instances returns Difficulty ID 2
• Running into Violet Hold & Utgarde Pinnacle returns Difficulty ID 2.
  More instances yet to be tested

LFG/RDF instances were checked with:

local activities = C_LFGList.GetAvailableActivities(2)  

for _, activityID in ipairs(activities) do
   local activityInfo = C_LFGList.GetActivityInfoTable(activityID)
   
   if activityInfo['isHeroicActivity'] then
      print(activityInfo['fullName'], activityInfo['difficultyID'])
   end
end