There are several women with names similar to Wandelmodis connected to this pedigree. His mother is said to be Windemodis de Salins, daughter of Gui and Adele. His paternal grandmother is said to be Wandalmodis, daughter of Humbert and Windelmode.
I think it might be that a niece and aunt are being confused.
According to Wikipedia, Humbert's daughter Adela had a Wandalmodis who married an Engelbert, and it was Humbert's daughter Vandelmode who married Beraud.
https://fr.m.wikipedia.org/wiki/Humbert_Ier_de_Salins
Humbert I st Salins (905 - 957/58), also named Humbert Macon, Lord Salins from 943 to 957 . He marries Wandelmodis, daughter of Gui d'Escuens, from whom he has:
Humbert II ,
Adela, she will have Wandalmodis (c. 960-) married in 985 to Engelbert III de Brienne ,
Vandelmode, (c. 920 - 957), she married Beraud de Beaujeu , (? - before 967).
According to Medlands, Humbert's daughter Adela had a Wandalmodis who married an Engelbert, and it was Humbert's daughter Wandalmodis (Vandelmode) who married Beraud..
http://fmg.ac/Projects/MedLands/burgkcounty.htm#Wandalmodisdied957
HUMBERT I de Mâcon, son of AUBRY [I] [de Narbonne] Comte de Mâcon & his wife Tolana de Mâcon (-before 958).
m [WANDALMODIS, daughter of ---.
Humbert & his wife had [three] children:
1. HUMBERT [II] de Salins (-25 Jul, after Jan 971
2. ADELA . m ---. Adela & her husband had one child:
a) WANDALMODIS . m as his first wife, ENGELBERT [II] de Brienne, son of [ENGELBERT [I] Comte [de Brienne] & his wife ---] (-1008 or after).
3. [WANDALMODIS (-after [987/96]). Chaume proposed that Wandalmodis, wife of Bérard de Beaujeu, was the daughter of Humbert de Salins, for onomastic reasons because of her own name as well as the names of her son Humbert and grandson Letaud m BERARD Seigneur de Beaujeu, son of --- (-[9 Dec 961/966]).]
Both sources state it was Wandelmodis the daughter of Humbert I who married Berard.
Both sources state it was Wandelmodis , the daughter of Humbert's daughter Adela (married to Gui de Tonnerre?), who married Engelbert de Brienne.
This Geni pedigree states Humbert's parents were Beraud II and Windemodis, and that his maternal grandparents are Gui of Tonnerre and Adele de Salins. Adele de Salins is shown as the child of Mayeul de Narbonne rather than Humbert de Salins as in the above examples.
His paternal Grandfather is another Beraud, who is ALSO married to a Wandalmodis, this one the daughter of Humbert de Salins and Wandelmodis, daughter of Gui d'Escuens
Should we consider that the parents of Humbert I de Beaujeu 960-1016 are Beraud II de Beaujeu 910-966 and Wandalmodis de Salins -aft 987 (the aunt), who was the daughter of Humbert I de Salins and Wandelmodis d'Escuens, rather than his mother being Windemodis de Salins (the niece) the daughter of Adele?
Should we consider the parents of Beraud were not Beraud I de Forez and Wandelmodis the daughter of Humbert I de Salins, but unknown?
Medlands does not give a father for Beraud II, nor does the following
http://www.beaujeu.fr/cities/326/documents/1tvtwr8bh0dzgxy.PDF
pg 3
Béraud (Berard), lord of Beaujeu
(reigned c. 929-966)
Little is known about this Béraud (or Bérard), a great owner
terrien, who married Wandelmode (or Wandalmonde) of Salins.
