Zaybein, who was visiting family in Napier from Upper Hutt, fell head-first while playing on the bouncy castle when an inflated column came loose and exposed a concrete hole, Ms Wathey said. Everyone heard a massive "thwack" when he hit the ground.
She said Inflatable World had been in touch to offer a discount of $6 because of the incident.
"A $6 refund is not going to solve my son. My son's not the same any more," she said.
Zaybein's stepfather, Paul Marjoribanks, saw the incident and "freaked out" after hearing the crack.
"When I was standing there and I saw the eyes roll back in his head, I've never seen my boy do anything like that. He had a bit of a seizure, then went all floppy and then just screamed.
"That lady who held him, in the hole, I thank her. She was just there for him. I need to thank her terribly."
Zaybein was slowly improving yesterday after being awake only for a couple of minutes at a time last week, Mr Marjoribanks said.
He was able to talk and his memory was intact but a simple game of Connect Four sent the "shattered" youngster to sleep for almost five hours.
The family hoped he might be able to return home on Thursday.
Ms Wathey said Inflatable World should be pitching in for the bills because of the incident.
She said it was unbelievable the accident came days after Deacon Rambaud, 4, was sucked under the bouncy castle at the Glenfield Inflatable World. A video of the incident on Facebook has received more than 1 million views.
It is understood another person broke their leg at the Napier Inflatable World an hour after Zaybein's incident.
Inflatable World director Gary Adamson said both Napier incidents were being investigated by the company in conjunction with WorkSafe.
Management closed the fun park yesterday while it fully investigated the safety procedures in place, he said.
An ACC spokeswoman said there had been approximately 774 incidents relating to bouncy castles or inflatable objects last year and about 392 so far this year.
