Redfearn linked up with the Magpies in the summer but walked out after just six months in the job.
Dawson told the Evening Chronicle: “We made a lot of changes over the summer.
“We restructured and tried to get things in place.
“Neil made the decision - it was his choice to leave.
“We will reassess the situation and get our heads together in terms of senior staff over the next few weeks and decide how we go forward."
For now Dawson and Liam Bramley will look after the reserves.
The Geordie coach added: “Ultimately at any football club the players are the most important thing.
“For our group at the Academy they're development is not halted.
“We need to build momentum and build off the back of a good performance at Port Vale and look forward to a busy period."