Yeah, my bad. But really, I'll be a participant on that contest, not a judge, so it isn't up to me to give the final word on judging an entry idea.
Maybe your idea does feel like a squad. But the CHARACTERS should be the main thing. Your other model you showed me, the big one, two guys are operating that machine. Does it fit for a squad? Maybe yes, but terribly. The first thing you think there is: goblin war machine. (it isn't even meant to be a squad, I'm using as example)
If your goblin gunner squad only use their wheels to move around, maybe it ends up looking more like a team of 2 or 3 goblins that collaborate, rather than a machine operated by 2. You read the guidelines. If your own imagination and common sense give you a green light, go ahead.
And maybe my answer was an overreaction of being too tired to tell people - no, an elephant riding a bicycle doesn't cound for a squad.