Imaam’s wudhu breaks and if 2/3 people are reading namaaz

Assalam o alaikum,
Respected Mufti Saheb, I want to know the ruling on imamat. Suppose a person who is doing imamat passed wind in between the salah say in sajdah then what will he do. just get up and walk away? What will the muqtadis do in this case and especially when they do not know that the imam is gone will they get up from sajdah on their own. Who will lead the prayers? Will the salah have to be broken by all the muqtadis and re-start again. What should be done in this type of situation?