Were there any Companions of the Prophet, peace and blessings be upon him, from the Indian subcontinent or China, and is what is claimed on Wikipedia about names like Tamim al-Ansari, Cheraman Perumal, and Malik Dinar true?

The "Wikipedia" website is not a valid jurisprudential reference. None of the companions of the Prophet, peace and blessings be upon him, were from India or China, because Islam did not enter these countries until long after his death, and no emigration from these regions to the Prophet was well-known. Some imposters from India falsely claimed companionship, including: Ratan al-Hindi, Sarbatak the King of India, and Jakrowani Farmas. As for the narration about the King of India gifting ginger, it is a Munkar (rejected) hadith due to the weakness of its narrators. The first Muslim invasion of India was in the year 44 AH. Tamim al-Ansari was a companion from Medina, not from India or China. Malik al-Dar was a Tabi'i (successor) from Medina, not a companion. The names "Sherman" and "Bromal" do not exist in Islamic biographical literature.