I am currently taking steps into trying to replicate this bug.
So far I am on my 8th battle on ENDLESS MODE on the Battle Tower, and I have not received this crash.
Once I lose (or my computer decides to death-loop again), I'll try CHALLENGE MODE and see if the issue lies there. If not, then I'll set this to Unable to Reproduce.
After 5 battles under CHALLENGE MODE before my computer death-looped again, I can distinctly say that I never encountered this crash.
Applying the Unable to Reproduce tag.