I never use wetwipes for my baby unless when we go out.
at home..i use warm water in cotton bud, and dry with tissue..
then apply densitin cream from her birth till now 3 months old.
that helps a lot to prevent nappy rash.
my friend even use black tea to wipes her baby..she said it's good to prevent nappy rash..but i prefer warm water instead..i thin tea is quite drying..
but you can give a try since she is already having such a rash