I used a Daitch-Mokotoff search
on the JewishGen Gazatter (more places, less specifically Jewish)
and searched on only the consonants in the name (VDGR).
The search returned a long list, but these are the places in Lithuania:
You can check each one out on Google maps to see which ones are close to Pasvalys and/or Ponevezh.
You didn't include your grandfather's date of birth, but it is possible that they were the only Jews in town so that there is not much research on that place. Or, they may have other records recorded as part of the Jewish community in a nearby town.
Keep us posted on what you find!
Peggy Mosinger Freedman