Corporations pay tax on their profits not, revenue. Employees have already been paid and customers have already bought before these taxes are levied. (The first bit is of course more complicated; for example, salaries paid for R&D don't always count as a deductible business expense.)
The market price is the market price. If corporations could raise prices further (even without new taxes) without losing customers, they would. If corporations end up being taxed more, raising prices in order to "pass on" those taxes will just cause them to lose customers, and end up with lower revenue (and likely profit too), perhaps even more than if they just sucked it up, paid their taxes, and left prices alone.
> If the argument is that tariffs are passed on to the customer, then corporate tax is definitely passed on to the customer and the employee
No, because they're not the same thing. Taxes, as I said, are applied only to profits. Tariffs are essentially in increase in COGS. They more or less require corporations to increase prices, with the expectation that sales will decrease. (They can also choose not to raise prices, and live with lower profits, if they have the margin to do so.) And this is the actual point of tariffs: to get people to buy less of that particular good, and presumably buy more of a similar locally-produced good. (The problem, of course, is when the locally-produced good already has a higher price, so everyone either has to pay more, or do without.)