The 5 Alien queens could propably do it by their selves. I mean, they're at least on the 50 ton range. And if Thing harms them, (which is rather difficult because Aliens are very resilent against blunt force trauma) they would bleed on him.
Their plasma would be sufficent to harm thing, plasma has been compared to the Star's core, but I doubt these projectiles are that hot. But still enough to penetrate his skin.
you're seriously underestimating the Aliens and Predators here.