I am still confused. In what context would any English speaker refer to 'this' accident? I feel like a big complainer, but the fact is that TO, TA and TEN don't translate so definitely to THIS. If I am wrong about this, please, someone, give me a clue.
'this' one that we have been talking about? I don't know. Perhaps an English speaker wouldn't.
We have to keep the direct translation of "ten" and "tamten" consistent, so that's why the main translation of "tego wypadku" will always be "this accident", with "that accident" and "the accident" being accepted. Sometimes it will result in unnatural English sentences, but if we weren't consistent, everyone would get totally lost.
...except "that accident" was not accepted when I just tried it now. Is there another reason in this case, or was it just not added yet?