Child Care FSA while divorced

[zivickim]

I am divorced and this is my year to claim my son.  My ex told me I am able to claim the full amount of daycare expenses, including the half that he paid.  Daycare has been providing me with statements for only my half and this is what I based my DCFSA on.  Now I want to know what I am really able to claim and how I could adjust my FSA to add the additional amount he paid.  Also, I believe I'm only allowed to claim up to 2500 being single, or am I allowed to claim the whole 5000? Thank you