Can the discharge from Her Option Cryoablation cause vaginal irritation?

You can definitely be experiencing vaginal irritation from either the extra moisture from the watery discharge, the procedure, from the pads, or all the above.

A "Summary of safety and effectiveness data from the Her Option Uterine Cryoblation Therapy System (2001)" states:
"Adverse Events at 2 week Post-Procedure" included 3% (5 of the 186 study participants) who experienced a UTI (urinary tract infection) and 1% (2 of the 186 women) who experienced vaginal infection.

Interestingly, the adverse events at 3, 6, adn 12 months post-procedure increased for vaginal infection to 4% (7 of the 186).

The vaginal infections experienced by women in this study were "managed with oral antibiotics."

It would be advised to call your doctor, and let him/her know that you are experiencing vaginal irritation, that you are concerned could be a vaginal infection, and ask what s/he recommends. I can also provide you with more information between the difference of irritation vs. infection, but would need to know more specifically what types of symptoms you are experiencing.

Hope to hear back from you soon!