PVA on it's own isn't good enough I'm afraid because PVA has an anoying tendency to revert to a semi-liquid state when immersed in water for even relatively short perods, and you may find that the joint further down has bonded and can't be broken without damage occurring. From my perspective if I were refitting I'd advise replacing the top(s). Probably something you don't want to hear, but in my case I don't want a boomerang job which I'll need to return to.
If/when you remake the joint by all means use PVA for the bottom of the joint (but only ever the Exterior grade, D3, like Evostik BLUE) but bond the top and front of the joint with either ColorBond coloured worktop jointing compound or something similar (available from Trend stockists, Travis Perkins, Woodfit, Unika, etc) or even a good quality silicone sealant. For black/dark grey worktops I favour Evostik Trade silicone, not the cheapest, but sticks like **** and seals well in my experience.
Scrit