Does the emission of moisture from the anus invalidate ablution, even if it has no odor, and could it be sweat?

The moisture that confused you, and you did not know whether it was sweat or moisture coming out of the anus, does not invalidate ablution; because the default is that ablution is not invalidated until a nullifier is certain to have occurred. As stated in the agreed-upon Hadith: "He should not leave until he hears a sound or perceives a smell." The meaning of this is the existence of one of them, and hearing or smelling is not a condition, by the consensus of Muslims. This Hadith is a great principle among the rules of Islamic jurisprudence, which states that things are judged to remain in their original state until the contrary is certain, and an incidental doubt does not harm them.