The family also claims none of the medical tests, for which Luke had been transferred to Alder Hey, had taken place.
Mrs Kirkwood said: "Ruth was basically told it would be held against her if she stopped Luke going for this assessment of his feeding. They got there and none of this happened.
"Within 48 hours they had decided to go to the High Court."
A spokesman for Ysbyty Gwynedd said about the nurses: "The pay is not the issue, the finding is the issue. Paying for them is not relevant. We've been funding specialist agency staff for Luke since March and that has not been a problem.
"Clearly the medical situation is the only factor in this, whether Luke is here or at Alder Hey. We are still actively pursuing agency staff, but the case is going to the High Court."
Talk of a High Court hearing came just days after a judge ruled in a virtually identical case little Charlotte Wyatt should be allowed to die.
The High Court hearing will take place in London next week before Dame Elizabeth Butler-Sloss, chairwoman of the Family Division. Luke's mum Ruth Winston-Jones
