The chapters are from third person perspective, and she couldn't have seen the island from afar given that she was in the cavern itself. I fail to see how this indicates that she can take 7-C attacks. She can do this as a last resort offense, but it's not a great showing of her defensive prowess.
Hazel Chapter 17
"Hazel summoned the last of her willpower. The air turned searing hot. The spire began to sink. Jewels and chunks of gold shot from the fissure with such force, they cracked the cavern walls and sent shrapnel flying, stinging Hazel's skin through her jacket.
Stop this! Gaea demanded. You cannot prevent his rise. At best, you will delay him—a few decades. Half a century. Would you trade your lives for that?
Hazel gave her an answer.
The last night, the raven had said.
The fissure exploded. The roof crumbled. Hazel sank into her mother's arms, into the darkness, as oil filled her lungs and the island collapsed into the bay."
I fail to see how scaling powers to physical stats is possible when most don't have showings on a similar scale.
Jason breaking his weapon made of magical explosive material and then tanking a small part of it is hardly 7-C, especially when he didn't expect to break it.
Jason Chapter 44
"He swept his spear sideways, met Jason's javelin—and with a snap like a shotgun blast, the golden weapon shattered.
The explosion was hotter than the giant's breath, blinding Jason with golden light. The force knocked him off his feet and squeezed the breath out of him.
When he regained his focus, he was sitting at the rim of a crater. Enceladus stood at the other side, staggering and confused. The javelin's destruction had released so much energy, it had blasted a perfect cone-shaped pit thirty feet deep, fusing the dirt and rock into a slick glassy substance.
Jason wasn't sure how he'd survived, but his clothes were steaming. He was out of energy. He had no weapon. And Enceladus was still very much alive.
Jason tried to get up, but his legs were like lead.
Enceladus blinked at the destruction, then laughed. "Impressive! Unfortunately, that was your last trick, demigod."
Enceladus leaped the crater in a single bound, planting his feet on either side of Jason. The giant raised his spear, its tip hovering six feet over Jason's chest."
The other clash involved Zeus/Jupiter's lightning and Jason is lightning proof as his son.