Bug Animations Transitions breaking models?

Hello, I'm currently working on a Fighting game in Unity 2018 (2018.2.2f1 specifically). I've started to use Unity's transition duration feature for some animations for a smoother transition between certain states (crouch to standing, standing to block etc) for a much smoother experience.

However occasionally the transition frames cause the models to break and distort in ways they shouldn't be. The clip below showcases this, there is a specific frame where the skeleton character's head and other parts break off from the body in random directions.

Here is a picture version of it since it'll be hard to see in video form



Afterwards the character transitions into the Blocking animation smoothly with no issues. Here's the transition part



I have a theory that it might be due to the character trying to transition to two animations at once (crouch and block) at the same time which may break it as it transitions. Really not sure however.

Any suggestions or better methods? or any idea on how to fix this/prevent it from happening.

 

I removed the interruption source and that seemingly fixed the issue, although Is there a way to interrupt a transition without using the interruption source?

 

That is an interesting theory.