My female lab has an ovarian remnant. Should she get surgery again?

I do recommend taking Aarfaa back to where she was spayed to have he remnant removed surgically. This is best performed when she is displaying signs of heat/ season - eg when she has a swollen vulva and or discharge. If it is left she will typically have heat cycles and be attractive to male dogs which can be a nuisance. Potentially she could develop an estrogen linked infection of the stump where here cervix was - this is called a stump pyometra. I understand your concern for putting her through surgery again, but in the long term it will be better for her.