You would be a lucky person if you made a traditional genealogy connection using just HVR1. Those 7 other matches are maternal line cousins but your shared ancestor may have lived many thousands of years ago. If two people match on both HVR1 and HVR2 and their maternal line is from the same geographic area and from about the same time, you have a better chance of making a connection but it is still difficult because surnames change each generation on the direct maternal line. However, if both maternal lines point to the same place and time and both ancestors have the same surnames then those ancestors may likely be sisters.
The Bahamas DNA Project http://home.comcast.net/~libpjr1/bahamasdna.html
has done pretty well testing mtDNA. There are 20 participants with mtDNA results who have direct maternal line ancestry from the Bahamas. 10 of the participants match one other participant (i.e. 5 matching pairs on HVR1 and HVR2). Those pairs likely share a matriarch who lived in the Bahamas. One pair was able to join their maternal line family trees.
Your husband's great grandmother is not Cherokee on her direct maternal line. It could be that her father's mother has Native American ancestry. To determine the origin of that mtDNA would require testing a cousin (male or female) who is a direct maternal line descendant of your husband's great grandmother's father's mother.
Peter J. Roberts
mtDNA Pin-Back Buttonshttp://home.comcast.net/~libpjr1/dnapins.htm