Is the verbal marriage that took place in Paris between a divorced woman and her colleague, in the presence of one Muslim and one Christian witness, and which was not officially documented, considered a valid, void, or corrupt marriage, especially given that the woman regrets it and does not wish to continue with it?

You erred by traveling without a mahram (unmarriageable kin) and accompanying a non-mahram man. You must make sincere repentance. As for the marriage, it is invalid because it was conducted without a wali (guardian) and with the testimony of non-Muslims. It must be annulled. If the man does not grant a divorce, then refer the matter to the Sharia judge.