The 5th chest in the VoG raid

So I was with some fellow raiding beasts the other day when we found out people are finding another chest (the 5th chest if you include the trick chest that gives spirit bloom). Our attempt at this chest was to try and keep the Templar boss from teleporting once. After we successfully did it with no teleports, we ran by the trick chest and found the 5th chest waiting there to be looted. I'm wondering if our method was the correct way or if anyone wants to clarify the process of spawning this chest feel free to leave an opinion.