Barrister Russell Clutterbuck said it arguably made the offending more "benign than a photograph".
"The difference between something which disappears and in 20 years can still exist … that's a very relevant circumstance," he said.
But Clutterbuck said despite being informed of the brevity of Snapchat during sentencing, the magistrate didn't change his position.
"It was a material fact … that should've caused him, in my submission to reconsider the matter," he said.
In a rare turn of events, counsel representing the chief of army agreed.
Philip Walker SC said the fact the video disappeared should have resulted in either the same or a lesser sentence, adding prison should be a last resort.
The court heard a sealed copy of Igoe's punishment was sent to his base at Amberley in southeast Queensland before it was read out by the magistrate in Canberra.
Walker SC said it demonstrated the sentence the magistrate imposed didn't change in light of the new information.
"It looks like, I hate to say this … that the defence force magistrate simply didn't take the matter into account and in fact still seems to be labouring under a misapprehension," he said.
"Not to be put to one side, the gravity of the consequence is 35 days' imprisonment."
Justice John Logan said while he hadn't made his decision, he was leaning towards sending Igoe's case back to the military to be re-heard before another magistrate.
Igoe, a graduate of Brisbane's prestigious Villanova College, has accepted his dismissal from the ADF but is not being held in custody.
The matter was adjourned to Monday, July 27.
