The Vizors are very remotely connected to my wife's family from that area, and she briefly looked into them - about 25 years ago! (NB - the surname is also found as Vizard, Vizar etc.)
There is a possibility that the two Josephs were cousins, both being descended from Arthur and Hannah Vizor of Easton Grey. However, this is just a possibility, not an established fact. Arthur of Easton Grey left a will, proved 1700, Archdeaconry of Wiltshire.
Research is inevitably a bit speculative, as registers are missing for some years, BTs are also patchy, and there aren't many wills to fill the gaps.