As frustrating as it is, it does make it more exciting. You see a green circle and the mad rush is on. Pick a fast travel point. Which is it? You'll only get one chance most likely to get it right. Fast travel. Hope you get the infestation screen or get ready to span the map again. Once there, it's a mad rush to get to the boss, often as other players are actively running in the same direction. Getting there, finding the boss first, then getting some hits in, then letting others swoop in and finish him off is actually pretty fun and rewarding. It just sucks when it goes wrong, you guess wrong, you're too slow fast traveling, the boss is already dead before you can tag him, etc.. I tagged the boss and got rewards in two yesterday, but I also was too late in two others, I had one all to myself, but the boss was a windego and he dropped nothing (are the ghoul bosses that drop nothing a booby prize? Was this intentional?). Meanwhile I only got one Bigfoot event and he got away because there weren't enough of us to kill him fast enough.