In short: if you’re using a Tenor in more than one clef, then you need to use the “Sounds as Written” Tenor instrument, with “Respect Octave Clefs” in Notation Options.
Your situation is a bit more complex, because you’ve altered the existing instrument definitions; but you need to bear these options in mind to get the right results.
TBH: I just use the “Sounds As Written” Tenor, with a C4 clef added to the start, and then I just delete it once I’m happy with the notes.