Always get permission before importing it into an other game! Some people didn’t do this with Locomotion and those people had a hard time ahead! Most of the people are willing enough for you to use it in this game, if you g ive them the proper credits (and respect).
I’ll probably ask Streamlines at some point since TF actually uses the 3d models, I could effectively be giving people the model, so I’ll see what the original makers think.