Suzy:

The only way to find out is to order the film (0245111) and see who the parents are. It is too bad that they did not extract the parents into the IGI for that film.

There are Delmas much closer to Zacatecas than Tamaulipas in Durango that may be the ancestors of this Victor:

JOSE FELIPE BENICIO DELMAS VILLANUEVA
Christening: 28 AUG 1842 Santiago Papasquiaro, Santiago Papasquiaro, Durango, Mexico
Parents:
Father: JUAN ANTO. DELMAS Family
Mother: PULINA VILLANUEVA
Batch No. C605212 Film 0654999

Delmas is a Catalan name... I have a good friend whose family has a pipe factory in Granollers in Calaunya.

What information did you find when you looked at the film for Soledad?
Didn't it list the grandparents? How about for Guadalupe?:

MA. SOLEDAD DELMAS SANDOVAL
Female

Event(s):
Birth:
Christening:
27 MAR 1869 El Sagrario Or Santo Domingo, Zacatecas, Zacatecas, Mexico
Death:
Burial:

Parents:
Father: VICTOR DELMAS Family
Mother: CONCEPN. SANDOVAL

Messages:
Extracted birth or christening record for the locality listed in the
record. The source records are usually arranged chronologically by the
birth or christening date.

Source Information:
Batch No.: Dates: Source Call No.: Type:
Printout Call No.: Type:
C600788 1870 - 1871 0245040

Suzy Burt wrote:
> I'd like to hear from anyone who might have info on this family. I believe that Victor must have been the son of Charles Francis Delmas - am I right? Below is all I know.
>
> Victor Delmas married Concepcion Sandoval about 22 June 1868 in El Sagrario or Santo Domingo, Zacatecas, Zacatecas, Mexico. Two daughters are known: Ma. Soledad, christened (same place as above) 27 March 1869; and Ma. Guadalupe, christened 12 June 1871. Soledad married David Diaz de Leon 16 February 1885 (same place as above).
>
> ~~~~~~~~~~~
> Suzy B. Burt
> ~~~~~~~~~~~