12:31 Rutherford's eyebrow scar on wrong side.
Dr. T'ana states that Rutherford's personality from a decade prior is attempting to overwrite his current one. The alternate personality is shown to have memories up to the accident which necessitated Rutherford's cybernetic implant. When the series started, Rutherford's implant was a new addition and he was still getting used to its functionality. This is just 2 years later, so there's no way his alternate personality could have been from a decade prior. It would be 2 years prior, at most.
Young Rutherford is seen wearing the cadet uniform introduced in 2374 at the time of his accident. Yet, when he is subsequently receiving medical attention for his injuries (and the installation of his cybernetic implant), a commanding officer is seen standing over him wearing a command-red uniform in the style of the TNG uniforms. Those uniforms were phased out more than a year before the introduction of the newer cadet uniforms. The fact that Rutherford was still getting used to his new implant at the start of Lower Decks suggests the accident happened closer to 2380 when the series is set.
Young Rutherford tells his older self that he funded his ship-building operation by winning Devron Races. The Federation doesn't use money.
After stunning Rutherford, Shaxs calls Dr. T'ana to the captain's yacht and mispronounces her name. T'ana is 3 syllables, (Tuh-ah-nuh), but Shaxs pronounces it with 2 (Tah-nuh). It would be bad enough for any crew member to mispronounce the name of one of the senior staff, but Shaxs has been shown to be in an intimate relationship with the doctor.
Rutherford asks Ensign Barnes about security shifts, somehow reasoning that her gold uniform indicates she works in security. Gold uniform indicates operations division, of which security is a part, but also includes several other departments. Notably, engineering is part of operations division, which Rutherford should know, since he himself is an engineer and is wearing a gold uniform.