Not much u can do then bro.. maybe try 4 plants in there next time just.. its very easy to over estimate your space.. ive been doing it constantly for 6 years now
better i think to do as many as u can with the right space than too many crammed in.. for these ones just keep as much space as u can between them til the end.. keep an eye on your humidity through flower and push them on towards the finish line
u could consider a good defoliation to open them up a bit and help airflow.. totally personal choice.. I would.. have you got a fan or 2 in there moving air??