Im making marrow rum?

Hi im making marrow rum/wine i put the mixture into demijohns and let the fermentation take place then i transfered the drink into bottles when i thought that the fermentation had finished after about four weeks. I corked the bottles and left them in the kitchen to stand for a while, but the rum has reactivated and has blown the corks off the bottles. So i am thinking should i put in a campden tablet to kill the frermentation in the bottles or just leave the corks off and put balloons on the top till i can get some pressure release corks. Can anyone help with the this. ( i put in yeast to help with the fermentation which is what i was advised to do) thanks. Rob