Count William II of Auvergne - Why is Aliedis his mother?

Quite a few other sites say that Robert's (other) wife Guillemette de Comborn is.

Medieval Lands says that (presumably Robert) the Dauphin d;Auvergne only married _ de Montferrand, and Guillemette is a Dame de Montferrand, and that Robert and his first wife had Gillaume II

https://fmg.ac/Projects/MedLands/AUVERGNE.htm#_Toc55890153

DAUPHIN d'Auvergne (-22 Mar 1235) ... m G--- [de Montferrand], daughter of ---.

Dauphin & his first wife had [five] children:

a) GUILLAUME [II] de Clermont (-[17 Oct 1239/19 Nov 1240]).

*** Perhaps Guillaume d'Auvergne is getting confused with this one?

https://fmg.ac/Projects/MedLands/provvaldi.htm#_Toc97476351

GUILLAUME [II] de Forcalquier (-[7 Oct] 1209 or after) ... m ADELAIDE de Béziers,