This is just an educated guess, meaning I give no guarantee, but I think that you should be able to test it localy. The problem with flock over nfs is that only the process(or possibly computer) that issues the lock will know about the lock. But since you will be the only user on your local machine it doesn't matter.

If you are unlucky flock will return false when on nfs which could result in fatal errors, depending on it's usage in Lucene. But I don't think this will be a problem.