Two RR15s? Missing D1? What the fuck man, this model...
I don't have a clue who or when sjaiswal created or modified this thing, but apparently it's been bumping around the internet for about that many years and still has this bug. No one tried to use it, or figure out what was wrong with it and correct it?
Anyway, try copying ".MODEL D12 D(" and so on until "+)" into the .SUBCKT TFF_TL493 scope.
SPICE is a scoped language, so MODELs only apply within a SUBCKT.
Man, so many SPICE models are
so bad... I'd love to investigate them, fix 'em up and put it on my website for free. If only I had some... motivation
Tim