Yes. Vishwaroop is the Hindi dubbed version. The time codes are completely different. Always download subtitles matching the (Tamil original). If you download a subtitle for Vishwaroop , it will not sync with the Tamil version.
Yes. The sequel, Vishwaroopam 2 (2018), also has English subtitles available on the same databases. Follow the same steps. Vishwaroopam English Subtitles Download
Introduction: Why Subtitles Matter for Vishwaroopam Vishwaroopam 2 (2018)
This is an encoding issue. Open the .srt file in and change encoding to UTF-8 . Then save and reload in VLC. Vishwaroopam English Subtitles Download