I don't read Spanish, so I can't be certain, but everything I have been able to read lists Nuno / Munio's wife as Argilo. I haven't seen anything listing Theuda Urraquez as his wife or ancestress of the people listed in this excerpt:
"Munio and Argilo are thought to have been grandparents (or more distant ancestors) of Castilian counts Munio Núñez and Roa, Gonzalo Fernández of Lara and Nuño Fernández of Amaya, as well as of Muniadomna Núñez, queen to García I of León."
That's from this site:
https://en.wikipedia.org/wiki/Nu%C3%B1o_Rasura
This site also lists Argilo as his wife:
http://cybergata.com/roots/4394.htm
Any clarification / correction would be appreciated. Thanks.