What is required of one who found green discharge after completing 'Umrah, and does not know whether it occurred during or after ṭawāf? And is the intention of exiting iḥrām sufficient at the time of iḥrām by saying: "Labbayka Allāhumma 'Umratan, fa in ḥabasanī ḥābis fa-maḥillī ḥaythu ḥabastanī"?

If the discharge is likely to occur at one of two times, it is attributed to the latter. Since you are unsure whether it occurred before or after you finished the Tawaf (definition), it is presumed to have occurred after you finished, and your Umrah (definition) is valid. These normal discharges invalidate ablution according to the majority of scholars. If they reach the level of incontinence (sals), it is sufficient for the affected person to perform ablution after the time for prayer begins and pray until the time for prayer ends.