You are correct.
But that doesn’t mean it’s not an occult satanic symbol.
The rainbow was mentioned in God’s inerrant Word. Now that the gay rights people have co-opted it, does that make its previous meaning wrong? No, it does not.
Likewise with checkered floors. You’d have to document for me that the Mason’s cultural appropriation of such flooring preceded the widespread adoption of the design before you would catch me flatly declaring it satanic, as you have done.