Could swollen lymph nodes with normal CBC in neck be from wisdome tooth extraction 10months ago? Had bad infection & hole in sinuses at the time

Not likely. Even if it took longer to heal (hole in sinus and infection), it is not likely that you would have a persistent swollen lymph node, assuming that it eventually did in fact heal. This is especially true if you have not experienced any other symptoms since then (over the 10 months). This doesn't rule out having a swollen lymph node from another separate dental infection. Have you had a recent cold?
Lymphadenopathy. If you have persistently enlarged lymph nodes in the cervical chain it would be advisable to have this looked at by an experienced clinician. Most are quite benign, but can also be suggestive of potential problems.
Unlikely. I do not think that infection that happened 10 months ago and already resolved be the most likely explanation of the lymph nodes enlargement- unless- if you are telling me that you are still suffering from the infection even until now. How big are the lymph nodes? Painful? Painless? Do you have cavities- inflammation on the gum etc?. Go to see your primary care doctor and get some evaluation.