"Being late to submit an application" isn't a protected characteristic. If you have enough good candidates within the deadline, proceed with those who remembered to attach a CV. But if not, go ahead and ask this one to send it.
Getting too wrapped up in what's "fair" (in the colloquial rather than legal sense) can lead you to ignore what's in the best interests of your employer.
Hello, in the past I have all sorts of "alternate" CV's attached - family recipes, photographs and a PDF of a mock up wedding invitation.
I'd suggest - like others - the choice is yours. If you have sufficient CV's to make a decision then go ahead with the ones you have, or if you don't or have the time to go back to the candidate then do.