At yesterday's court appearance, Sergeant Chris Goodall advised Judge Keith de Ridder to formally withdraw the lead charge; this was unopposed by defence lawyer John Day.
Welsh appeared in full protective gear via an audiovisual link from a remand facility.
Day asked the court for sentencing to be adjourned as Welsh's third and final Covid test result was expected tomorrow.
The previous two tests came back negative, he said.
A police summary of facts said Welsh's friend arrived from Australia and was taken to the Crowne Plaza hotel in central Auckland to undertake a 14-day quarantine.
While his friend was in an outdoor recreational area surrounded by temporary wire fencing, Welsh approached him about 12.20pm on August 7 and pulled at the fence which caused the panels to separate.
He made his way through the gap in the fence and entered a quarantine area.
The pair hugged each other for one or two seconds before police approached Welsh.
He refused to engage with police, got into his vehicle, and drove off.
Welsh was arrested the next day in Whangārei.
He told police he knew he should not have gone inside the quarantine area.
Head of managed isolation and quarantine Air Commodore Darryn Webb said at the time Welsh was arrested that his actions in putting others at potential risk were incredibly irresponsible.