Differential blowed out?

I drove the truck about 45 miles and had to get it back to the yard. Yesterday fueled up and noticed a noise that seemed off got back to the yard some a little seap from pinion seal. Truck sat for a month so thought maybe it was from sitting. Well check on it this morning and saw all this. Got it back to the yard drove fine. Would all this gear oil be just from a seal or my pinion bearing is shot? Gonna have the shop look on Monday I’m just trying to prepare myself I just had to do the rear axel and a few more things and the last few months so really don’t want the news I need to replace diff

 

When you say tearing into it would they have to open it up and take the diff out? I was checking out the drive shaft when I stopped and tried moving it up and down and side to side and there was barely any play when my rear went out there was a lot of play in that one but this one very minimal