Marshall announced he will depart the club at the end of the season, following Saturday’s 4-0 win over Selby.
The Badgers boss said the moment he broke the news to his players was his ‘worst in football’.
Wyles released a statement on Monday which revealed the club needs to raise £5,000 for the first team account by the end of the season.
In a full and frank interview regarding his position at the club, Marshall said bluntly: “I stick to my word.”
“I had agreed expenses for players at the start of the season but the travelling expenses stopped in November, and since then I have taken on that myself.”
“That’s four months travel expenses owed to me, I pay for us to use the training facilities too, the football club hasn’t really given me a penny since Christmas.”
His United side currently sit second in the NCEL Premier behind Bridlington Town following Saturday’s 4-0 win over Selby Town.
The resignation would see both Marshall and his assistant Graham Walker step down after their final game of the season against Bridlington on 28th April.
And the manager said the players’ commitment to the club could not be questioned.
“We have gone top since all the money stopped in November,” said Marshall.
“If anyone could understand what it took for me to stand up in front of the players, who are friends too, and tell them I was going to resign - it was my worst ever moment in football.”
“I have nothing but fond memories of the club, and if finance came into the club, I would love to stay.”
Marshall says he has received numerous phone calls of support from people associated with the club.
“The fans are fantastic. Wherever we go they are there and I really feel for them,” he added.
“As an ex-player, it was the proudest moment in football to come back. But since November it’s been the worst time of my career.”
Wyles said he is yet to receive a formal resignation from Marshall, but said his intention to leave would be a ‘great loss to the club’.
In a statement published on Monday, he said: “Brett has been let down and as chairman I take ultimate responsibility but I will continue to do everything possible to bring in the funds for the expenses and monies owed.”
“Little has changed since the fans forum a few weeks ago where the situation was discussed with everyone stating their view point.”
“Two or three regular contributors have come forward to help run the club.”
“Unfortunately, the facts are it is still the old debts that are dragging the club down.”
“I want Brett to stay, the players want Brett to stay, and most of the fans want Brett to stay.”
Wyles added: “The club will always be here, whether I’m there or not, the club will always be here.”
A forum is to be announced shortly where fans can ask questions to the chairman.
For Wyles’ full statement visit www.retfordtoday.co.uk.