The former St Pat's star has been at home in Dublin for the last three weeks after being granted compassionate leave due to family issues.
"I've had to deal with this nonsense on Twitter and I am disgusted by it," Clark said. "The lad has an issue with his family and it is a personal situation. His going home has nothing to do with me having a fall out with him. I have huge respect for Keith. Unfortunately this Twitter business shows the modern society we are in. Keith has an issue back home. That is why he isn't here."