Got one too and mine was 30 dna.
That’s strange everyone else who has got legendary or Unique DNA has got equal to their level. Notice this guy got 16 DNA at L16. I recently scored 19 Spinotasuchus when I was L19 (left me with Thant annoying 9 at the end). Not calling you out, I just didn’t think it was possible.
I was going to take a screen shot of it but didn’t think it was that much so I didn’t bother.