It is a sales tax, they're just pretending that it will be paid by the seller--as though corps will just take a 3% hit on profit margin! The only differences I can see are A) the tax will be obfuscated (i.e. baked into the sales price, or shifted from low-margin to high-margin items), rather than neatly listed as a line item on the receipt, and B) businesses with revenue under 25M are exempt.
Sales taxes are typically a geographic boundary and a product inclusion/exclusion list. The addition of “seller’s annual revenue” may not fit within existing legal definitions (I haven’t checked), and I expect that naming it a “corporate tax” serves various marketing purposes (both for the headline’s author, and for the proposal’s authors).
You only need a subsidiary in Oregon. So all major components get moved outside the state, including higher wage jobs, and leave bare minimum distribution in Oregon. Which undoubtedly contracts with another out of state subsidiary for "marketing" to ensure profits are below the 25m threshold.