Having trouble with this theory

I can get on board with the idea that the Vikings explored the area 900 years ago. There's a permanent settlement 200 miles away from that time period. Absolutely I can see they didn't stay in that one place - they still had boats and continued to explore further down the coast line to Nova Scotia - totally feasible.

Not sure how we get to a(nother) roman coin from 1,000 years ago made to Oak Island because the Vikings transported the Templar treasure there. Can some please explain that to me like I'm 5 so it makes sense.

Feels like there was one tin foil hat theory on the trip to Europe last season and now "that has to be it!" - Prove it.

And can we please stop acting like if an artifact is dated to be old that it's been on the island that long. The lead cross dated to the 1300's - it wasn't made in that spot on the island. It fell out of a pocket who knows how long afterwards.