They are completely different. If Wiab was made as part of the SG universe, then why was it abandoned instead of reworked? Wiab and Wiab2 are connected only by the appearance of the characters.Uh, no.
WIAB, even the original (or -1 according to you) version was ALWAYS meant to be in the same story universe as SG and somewhat of a "prequel" to SG.
Everything is complicated here and you are confused. Wiab1 (abandoned) couldn't possibly be a prequel because it came out earlier. Remember, the first released part is the main one. All parts released after the main one are divided into sequels and prequels.
If you take for the main part of Wiab1 then SG becomes its sequel. Since Wiab1 was abandoned, it is not taken into account. The next in line SG becomes the main part and Wiab2 becomes the prequel.