From what I see here, there's "days_since_install", "most_consecutive_login_days", and "last_activity_date" which is all visible in the profile (also "snapshot_date" to adjust the website's delay).
But you need the name to access that data, something DSP has refused to give. If he were to give one now, it could potentially be from a bought account (there's like a "black market" for these: you see the ad, contact the person through Discord/whatever and arrange an account transfer. This is not permitted by Scopely, but as long as you get away with it).
So like Bigbadyeet was saying, but he has to make sure he does not screw up a couple of things in the process. If done correctly with an appropriate account, he can discredit the evidence and those who don't know any better, could believe him.
If he does this and you mention it, his response will be that you're "moving the goalpost".