Does that dino have IK on feet?
Select that creature, go to menu - FIGURE and select USE INVERSE KINEMATIC - are there any entries under that submenu?

My guess is that NO.

It happens like that if you apply a pose from a figure with IK goals to the figure without IK goals (no IK goals inside cr2 file)

The default poses for walk designer are made from figures with IK goals (and with IK switched on).

But it can be something else as well :)