I have repeatedly answered your question. I think the issue is that you just don't like the answer which is 'no' for the reasons that I have set out. I have dodged nothing - I have simply disagreed with you.
The problem is with your insistence that we forget about the real world in which businesses operate and try to treat taxation as the only factor that influences decisions.
It isn't.
The problem can be demonstrated by your argument that:
ours is at 20%, Germany's at 30%, given that, our goods are potentially 10% cheaper, of course the extra costs of exporting those goods to Germany could be considered, that doesn't take away from the fact that we're still cheaper in terms of corporation tax.
Putting it as neutrally as I can, your argument is nonsense. The element of the price of a car that will eventually be paid (as a percentage of the profit that is made on it's sale) is tiny when compared with the cost of making it. It follows that to suggest that the fact that a countries corporate tax rate is 10% lower than the UK means that a car sold there is 'potentially 10% cheaper' makes no sense at all.
Let me try one more analogy in the hope of showing you problem with you argument: If the company that supplies your water put up iyour bill by 10%, it would not be correct to say that your household bills have gone up by 10% as the increase applies to only a proportion of those bills. The same applies to the situation you describe: the Corporation Tax element of the price of an item - the element of that price that will give to the taxman as a percentage of any profit made - will almost always be dwarfed by other costs.
We run a huge and ever increasing trade deficit on goods with the EU, that is only partly offset by a surplus on services. In part that is down to the geographical handicap.