No O-ring inside gator?

[NX-STEP]

After taking off the driveshaft on the near side, there was no o-ring on the inside of the gator? I see a vid on youtube (1.2 clio)about replacing driveshaft n/s and he took the o-ring out to remove the flange plate from the gator.

is this why the gator won't sit properly in the flange plate on the n/s driveshaft I'm replacing?

Any help please... gotta fix this like yesterday.