Should I check BG/Credit on both parties?

[Maria Crenshaw]

An engaged couple has applied to rent. She will not be working and he has a good job, great credit, etc. He submitted  Credit and background reports for himself but she did not. His information looks great - superior credit and clean BG. These reports cost them so I don't want to ask her to submit them also unless there is a good reason. My gut tells me to let it go. Thoughts?