The two booking agents accused of health and safety failings in the Whakaari / White Island trial are applying to have their charges dismissed.
ID Tours and Tauranga Tourism Services Limited (TTSL) made submissions in the Auckland District Court on Wednesday.
ID Tours' lawyer David Neutze said WorkSafe's case was confusing and conflicting.
"Even after six or seven weeks of evidence and at the end of the prosecution case, my submission is it's still entirely unclear what the 'appropriately detailed and up-to-date health and safety information about tours on Whakaari' ID Tours was legally obliged to provide to Royal Caribbean," Neutze said.
"Nor is it at all clear it was reasonably practical to ensure that this 'appropriately detailed and up-to-date information' was provided to Royal Caribbean's passengers.
"A big hole in the prosecution evidence is that we have no evidence from Royal Caribbean about what their requirements were."
It is the second time ID Tours has made a submission to have the charges dismissed.
TTSL lawyer Sarah Wroe submitted that many of Neutze's comments could be applied to her client too.
Both she and Neutze were critical of the charging document, which alleges they did not work with each other and White Island Tours to get appropriate and up-to-date health and safety information about tours on Whakaari and ensure it was given to Royal Caribbean cruise passengers.
"It is very vague and loose and I highlight that by reference to the 'appropriately detailed and up-to-date health and safety information', whatever that might be," Neutze said.
"It is perverse for WorkSafe to now suggest the duty to somehow ensure that someone else's passengers received information that it did not have, could not be reasonably expected to know and was not expected to ascertain."
He said WorkSafe opened its case saying ID Tours did not have a duty to ensure the tour was safe, conduct risk assessments or ensure controls were implemented.
Neutze said some of the evidence in the trial had been that tours to the volcano should never have been run, which was not ID Tours' responsibility.
"What is it that ID Tours was meant to do? They weren't meant to do risk assessments. They weren't meant to decide whether the tours were safe, but somehow they were to provide appropriate and up-to-date safety information, whatever that is.
"Health and safety of the tourists on the tours ... was simply not part of the ID Tours work activity."
Wroe said WorkSafe was approaching the case with hindsight: "Looking back to see whose actions could have been done differently to have made a difference to these tourists. That's not the appropriate way of doing it."
WorkSafe will make its reply to the submissions on Thursday.
The submissions come a day after the owners of White Island Andrew, Peter and James Buttle, had their charges dismissed.
Their company, Whakaari Management Limited still faces charges.