Because this is "uncut" content, it is not available on their main public YouTube channel due to copyright and length. You can find it through their subscription platforms:
This is the primary hub for their "Uncut" series. You generally need to be subscribed to a specific tier (often the "Movie Watchalong" or equivalent tier) to access the full-length video file or private link. Watch Thallumaala Watchalong Patreon and Members Uncut
You must already own or have access to the movie Thallumaala (currently streaming on Netflix ) to watch it along with them, as they do not show the full movie footage in the reaction window to avoid copyright strikes. Because this is "uncut" content, it is not