I don't know what it is but Red Templar's have been bugged since launch with "key no drops" and round 5 incompletes so no, it's not just the dogs. It might be an issue that's even MORE present when dogs are combined with Red Templar but trust me, it's been there since launch and it's Red Templar specific. Like many have said the leading speculation is that is has to do with the Stalker stealth behavior not ever de-cloaking for some reason. I don't pretend to know what exactly it is but it's certainly faction specific.
Also, to point out the obvious, there's zero dogs/animals in Round 5 and how often are you guys able to trigger "round complete" successfully even after killing everything?
The invincible Shadow-bug has happened to me once or twice. Both times it has been in games where firestorm has just been used.
If I play with Ele's on the DLC it bugs out every second game. It does happen sometimes without firestorm-eles aswell, but for me maybe 1/10 or even less games bugs out for me when I dont play with Ele's.
have also solo'ed alot, because it makes it easier to accomplish certain acheivements, and with probably over 150+ solo games the ONLY time the games has had key drop bug has been while playing Ele and using firestorm. And then it happened twice in four games. I think the evidence is overwhelming.
And I have probably played about a 1000 games so far and I have been playing since the day after launch, I think I know what I'm talking about. I'm not just pulling this out of my a**.
But then again, you say that sometimes you cant even finish round 5 because of some bug - and this has NEVER, EVER (a credit to the game) happened to me, in all my game time. So some bugs might be down to something quite different, and be more individual somehow.