If the runway was in the UK and at a certified airport and you had not received a NOTAM declaring that it "may be slippery when wet" then you may have diverted for no reason.
The airport has been windy in the past..........
Thunderstorms are a known problem here......
Damp in a number of states has no basis, try AMS. It is just visible staining of the surface.
Was the runway constructed of skid resistant material eg PFC, GMA or BBA?
What is its LDA and, for your mass, what was your LDAr?
What is the name of your Flight Ops Director and does he serve biscuits when he has a "chat" with you?
Good luck!
Sir George Cayley