English Translation
She married him for his money.
“Cowok” with K is the right spelling, according to KBBI. “Cowok” means “a young guy” in a casual way.
“Cowo” without K is ranked 24,565th in the University of Leipzig Indonesian Corpus whereas “cowok” is 5,823rd. The example sentences and co-occurrence data suggest that “cowo” is probably slang.