Condor Ferries will operate a normal service over Easter despite not being able to charter a backup ferry, the company says.
It had been asked by the island governments to use Brittany Ferries after the Liberation was detained.
Acting CEO Ken Soar said it could not charter a boat as there were too many hurdles to overcome.
He said it would only have only brought in the Normandie Express in order to bolster public confidence.
Safety issues were found on the vessel, which was heading for Jersey and Guernsey, by Maritime Coastguard Agency (MCA) inspectors.
Mr Soar said it had contingency plans in place for the weekend in case things went wrong and its other vessel, the Condor Rapide, was back in service.
He said: "It was suggested we get the Normandie Express in but we just could not make it work for a number of reasons including a lack of crew.
"I need to apologise for what has been a dreadful year on our part; our customer service has not been up to where we want it to be.
"We want to provide a world-class ferry service and we will be a world-class ferry service."