Is the marriage contract void and must it be redone because of abandoning the 'Asr prayer, due to the Hadith: "Whoever abandons the 'Asr prayer, his deeds have been nullified"?

There is no need to remarry, and there is no ground for the invalidation of the marriage based on what you mentioned in the question. We fear that the question might be a result of waswasah (whispers from Satan or obsessive thoughts), and one must be cautious of it by ignoring it and not paying attention to it.