Wintergrasp bug/hacks?

So how is this possible? I was just defending wintergraps and suddently bam we lost without horde breaching our inner gates:
https://imgur.com/a/Epc7pIX

It is possible, and not only with a multiboxer bombing, i was on the outside defending our non-cheating vehicles, someone has been using a vehicles under the floor lately on both factions,
it's getting annoying, especially when an already semi easy win becomes bland by someone cheating their way to it.
I recommend everyone start recording and taking screenshots(you can turn on nameplates to show it better) when they see it, then Warmane might fix it so it can't be bugged like that, and ban whoever does it.

It is not a vehicle just lurking and bombing it from underground otherwise it would show it on the map or at least it would say that horde was controlling 1 vehicle which was not the case

Oh wait, i probably wasn't in that WG, the one i was in got won like 20 sec after we broke the last of the courtyard walls, but with inner wall already down by then,
maybe it was a multiboxer bombing in there, i know a few of us do it, and even within the rules because it's just supersizing engineering bomb damage with alot of characters, i do like 11% per hit with 30 saronite bombs, 22% with 30 goblin engi bombs