Bruce and Rhondda Langborne say they will continue "banging on doors" in order to visit their terminally ill son in Brisbane.
Mark, who will be 40 on September 30, has been diagnosed with small cell cancer.
Under current Queensland government COVID-19 regulations, the Langbornes say crossing the border to see their son would cost around $20,000.
"We would have to bear that cost," Mr Langborne said from his workplace in Eden. "Mark lives in Brisbane and we have been trying to get to see him for some time.
"He has four children in Sydney and we are desperately wanting to get them up to Brisbane to see their father before he gets in too bad of a way to interact with them.
"Mark is on chemotherapy treatment as a patient in the Prince Charles Hospital.
"It frustrates me that we just can't go and see him," Mr Langborne said.
Mark Langborne has lived in Queensland the past 12 months where he works as a truck driver.
What is also frustrating Mr Langborne is the continued mixed messages the Port Macquarie couple is receiving over their potential to visit their son.
He says the family was originally told that they could not enter the state to see Mark.
"Then we were told that we could see him, but we had to self-isolate before we could see him.
"As of today, we've been told that to see him we have to isolate in a hotel of their (the government's) choosing, and each of us - including the children - would need to wear full PPE (personal protection equipment).
"We would also be required to use a special taxi to and from the hospital," he said.
"We would have to bear the cost of that exercise, around $20,000."
Mr Langborne said people familiar with their plight have been very sympathetic.
"It is a pity that the government and the public servants just aren't listening," he said.
"I believe the (Queensland) state government should look at these matters on a case by case basis.
"This isn't like we want to visit someone that has the flu.
"Port Macquarie and Eden are both COVID-free areas, so it is not like we are wanting to come from a designated hotspot.
"You could understand why we would not be allowed to enter if we were (from a hotspot). But we aren't," he said.
"To be perfectly honest, we understand that there would be other people in the same kind of situation as us.
"So we will just keep banging on doors until they let us in."