Singleton informed the company on 20 October that he was resigning as an employee with immediate effect and would remain in place for the rest of the month.
He joined Swan Print on 2 November and will take on the role of business development.
However, he said that he has not been paid by Celinco for October.
He said: "During the first two weeks of October I became increasingly concerned by the lack of information available from the parent company Celinco.
"Despite many requests for clarification of the way in which the companies would operate, very little was forthcoming. I became increasingly concerned for the well being of the employees and creditors."
In October, Unite said it would take legal action against PBB and parent company Celinco over a series of alleged breaches of contract and unfair dismissal charges.
The union said it was to take action on behalf of four of its members in relation to allegations of unfair dismissal and that wages had not been paid for September and October.
PBB was bought out of administration by Celinco in September.
Celinco was unavailable for comment.