90% of Mumbai CST bound Mail/Express train don't have unscheduled halt at Thane. (Lokmanya Tilak Terminus bound trains do make halt of 30 seconds at Thane over pf no : 8)
Plus during morning hours when this train arrives local network is free from congestion so chances are probably nil so better alight at Kalyan.Jn, then take a local ride till Thane as locals travel will be pretty easy at that time due to less crowd & thereafter take any Panvel/Nerul/Vashi bound Trans-harbour local to reach Ghansoli.
Thanks!