Assalam Alaikum, Where does Islam stand on wearing swine (pig) leather clothes? And leather clothes that are likely to be of swine origin but the seller can neither confirm or exclude that possibility with confidence, like suede which most commonly is from cow but could also be from pig? Thank you.

All praise be to Allah, and may his peace and blessings be on the last and best prophet and messenger, Muhammad. The tanned hide of pigs is impure according to the stronger opinion of the majority, thus may not be used. If the suede as you mentioned is usually from cow's hides, then you may wear it even without being certain of its origin. Allah knows best.