I mean, Goku just casually switched back and forth the form in the battle against Freezer when he gave up in the fight, though I guess they didn't know at the time.
I mean, I would imagine not. Goku's eye color in his design was barely solified by that point, because Toriyama when first making it just had the hair up (as seen in Lord Slug) then made it blonde with red eyes (as seen in many prototype designs, which were even used on Cooler's Revenge Posters) before finally focusing onto one specific design (Blonde and Blue Eyes). The film also blatantly reused a cut of Goku's power up and attack against Frieza in the film, so I wouldn't be surprised if they straight up just weren't aware.
Yeah pretty sure the guys who made the movie which Toriyama didn't take much part in just didn't think Goku could easily go Super Saiyan after Namek."Goku becomes a Super Saiyan again." (Passage right next to the film poster). Confirming what was stated on the Toei Return of Cooler info Pamphlet/Film Comic, Goku used SSJ against Frieza, meaning the plot hole is doubly recitified.
I like to think this was Goku's first time using Super Saiyan after Namek in this alternate dimension, so he couldn't go to that mental head space of rage on his own.
