In a few cases, that water leak started with water pump R&R. Tightening them more never saved me either. Gasket failure, plain and simple ( or maybe not so simple ).
If the timing cover isn't pitted terribly a gasket kit will fix it. Many of the long bolts go into water jackets. Lets hope none are rusted so bad they break before backing out. Wire brush those bolts, clean and dry their holes, put sealant on their threads.
Snowballing ? How about a new timing set while in there ? Spring loaded chain tensioner too ? :) Good luck with it.
