Why don't we ever see _____'s _______?

Spoilers obviously and forgive me if this has already been discussed, but... Why don't we ever see Gemma's surname? I noticed this multiple times in the last episode, almost to the point they went out of their way to show us NOT showing us her surname when she's writing the intake form.

I thought the filming of the name plate on the door as Mark walked by was very clever, far too quick to even pause and see the name, and then we see her writing her name and it makes sure her hand covers the surname as she writes it.

My absolutely wild, out-there theory that I am positive will be Jossed come...whenever, is that she was going to write Cobel 😂 (in fact, Dichen Lachman is biracial, so her having a white parent wouldn't be a stretch!)

What're your thoughts? Why do we never see or hear it? I would've thought we'd at least see her write Scoutif it was no big deal?