Yes I have, the other remaining two are in the Maritimes area. I personally think at least one of those holy sites should be spread out into the middle of new england there somehwere. I know one of them should stay in the Maritimes because of the whole Nova-Scotia aspect (hell three of their duchies are directly celtic inspired names, Alba Nuadha, Nua-Shéalainn and Eileann Eóin. Methinks there was a MASSIVE revival of celtic traditions and languages in that region, including varients of Irish and Scottish Gaelic and their new world counterpart dialects, I think OTL Nova Scotia has their own dialect of Scot Gaelic too, being of Highlander stock originally, as does that oddball celtic colony somewhere in South America of I think Irish descent, which isnt on the game map anyway) bu there really should be one inbetween Boston and the Maritimes to make it a bit more sensible. I have no idea why Atholville is considered sacred to the Druidics being dead set in quebecois territory. This is simply a placement concern otherwise the territoroy fits perfectly.
I guess the two holy sites in Labrador and Newfoundland are there because those regions can more easily contact the old celtic fringes of Europe, via Greenland and Iceland trade routes, which while not represented in the Game lore or mechanics, would be a well known and well exploited route for the New American kingdoms. Although I imagine there'd only be cultural trade with Ireland and Scotland realistically, because apocalypse or no apocalypse theres no chance in hell of Scotland or Ireland ever going back to Druidics religion. Granted both are far more secular now than they were historically OTL, but neopaganism and new ageism has nowhere near the hold in the old countries as it does in the American north east OTL, so when the bombs fell, they'd far more likely go to some form of Christian heresies or take sides in the POPE FIGHTS on the continent. After all, America has only several centuries of Christianity, and a good portion of that under secular governments that didnt enforce religion, and were more thoroughly secularised into a near identity-less morass by OTL. Scotland and Ireland would have over 1500 years of hardcore Christianity steeped into their bones, willingly accepted and willingly self enforced for all of that time, even secularised today, they cant really just shake that, and in post-event world, would immediately return to their religious traditions due to neccessity.
That said however, Scotland OTL DOES have one of the biggest new age communities in Western Europe in terms of actual communes, if not proportionally in the wider scottish population, so druidics from North America going 'Across the High Road and the Low Road' to Scotland on pilgrimages would be an interesting event chain.