Yeah, it's not the material, it's the chewed off bits that I would be worried about. It would help you prototype something, then make a mold that you can use.
For my dog though, if it doesn't squeak, it doesn't exist.
I see your point about parts breaking apart being a concern.
How familiar are you with TPU? It’s quite durable and robust. It’s a plastic currently used in many dog toys. Between that and Part of me feels like TPU being a soft plastic that would minimize risk.
TPU prints are very robust for FDM prints, but dog toys need to be solid objects. Even a small dog will tear apart a printed toy. Layer adhesion is no match for dog teeth.
Printing a mold and then casting the toy would give much better results.
Pretty familiar, I also use it for prototyping. It's an awesome material, but FDM is no match for a dogs teeth.
I wouldn't want to take the risk, peraonally, but I guess it comes down to your level of risk tolerance and if you're absolutely confident it won't harm your pet