My understanding of the discussion at hand was that believing and being baptized, by so doing, are what saves the doer. If being saved actually occurs after that, and not immediately upon/from it, then the doing isn't and can't be what caused it. Instead, I think the verse is referring to attributes that come to someone as a result of salvation - with belief and the desire to be baptized as being some of those attributes - but not cause.
I think the being saved that is in view, was meant in the same sense as the verse below states it. Notice the "unto the end, the same shall be saved" - the "shall be saved" is future tense. It is telling us that the being saved is of the last day (the end)- that being saved in that context is to be saved (escaping) from the retribution of God on the last day. It is also the same future tense for those who will be damned in Mat 16:16. I think "shall be saved" (future tense) is found repeatedly throughout the New Testament. However, those who do escape, are only of those who have also already become saved during their lifetime, but not through their believing nor by their human baptism, otherwise, it would have had to be stated as being immediate and not future. That is, by being stated as future, believing and baptism are eliminated as the cause of salvation, but not as salvation's effect.
[Mat 24:13 KJV] 13 But he that shall endure unto the end, the same shall be saved.