1. He primarily fought them one at a time, not simultaneously, even though multiple heralds - Firelord, Terrax, Nova, and Air-Walker - were present.
2. He didn't no-sell Air-Walker's punch to the face, which suggests Green Scar would perform just as well, if not better.
3. He ripped off Air-Walker's arm and struck him with it, briefly held Firelord down, and knocked Firelord off his back. Green Scar could easily replicate these feats.
4. He used energy blasts (both with his axe and his hands), but energy attacks are irrelevant here.
5. He cut Firelord with his axe and Terrax with his arm blade - again, not relevant in a slugfest.
6. Nova knocked him out with a serious blast, and afterward, he attacked her from behind with an axe blast while she was talking to Surfer - also irrelevant here.
Nothing in that battle demonstrates he could defeat even Savage Hulk in a slugfest. He has no notable strength or durability feats relative to Green Scar.
Lastly, a lesson:
The specific details of a comic battle carry far more weight than its outcome. For instance, me defeating five Kryptonians with an omnidirectional Kryptonite blast doesn't mean I could "destroy" Hulk in a slugfest. Context and details matter, and the foundation of your argument is flawed.