Lhikan’s Hau, noble at the time, was shown to visibly shape ■■■■■ between Great and Noble appearances when placed upon Jaller.
As such, I believe that the Movies are simply an inaccurate visual representation, just in general.
I think what happened is, Lhikan’s Hau looked as it did when he wore it, and then, due to taking in Jaller’s unique Imprint, it changed shape. Said imprint is almost like an SD Card, as it stored Jaller’s Save Data essentially, allowing pure life energy to bring him back at his last save(his memories before death)
This is when things get unclear. It is possible that Lhikan’s Hau kept Jaller’s Save Data, but I think it’s possible that it could’ve been transferred into his Calix/Arthron when he swapped Masks, since otherwise we could have two Jallers running around.
However, I dunno if a Mask only has one slot for this save data, or multiple. If it did have more slots, then the Hau would likely revert to its original Lhikan Shape, and store his data. Or, alternatively, adding Jaller’s data wiped Lhikan’s data, and it has no data now. In which case, it would likely retain either Default Noble Hau shape(Lhikan’s Turaga Mask, as it were) or retain it’s normal Great-Looking form.
Someone asked Greg this on the Lego Message Boards. I believe he said something along the lines of; the only reason there is a difference is because set designers wanted a different looking Hau for Lhikan. In the story, most Hau(s) are more or less the same.