Can I verify a sub public key came from it's parent public key in a HD wallet without involving any private keys? I know I can sign a piece of text using a bitcoin private key to prove control over a public address but are there any operations I can perform to know if a public key submitted to me was derived from a parent public key if I do not have any private keys at my disposal?

I have looked at:
https://github.com/richardkiss/pycoin and 
https://github.com/jmcorgan/bip32utils
but have not yet found a way to do it.

Thank you for any input :)
Yes, you can, assuming that the child key isn't hardened, and you know the chain code of the parent public key and the index of the child. (Also known as the extended public key.)
Just compute

CKDpub((Kpar, cpar), i) → (Ki, ci)
Kpar is the parent public key, cpar is the chain code, i is the index, and Ki is the child public key

as defined here and compare it to the child key you were given.