I managed to remove two plugs from the cubes and very few tiny roots were lost. I trimmed off the infected material away from the seedling without harming them. Now it's sitting in a small plastic nanny cups. Maybe I'll keep em alive. I migh have to administer first aid to a third tone as well. It is tall enough for me to use something to block off the light as suggested (until I can get something proper I used black duct tape) waiting to see how long it takes to kill the ugly green carpet.