Swingarm failure - torque arm mounting point

[Skippernick]

Fitting a blue dot caliper would have nothing to do with it as it is fitted to the standard mounts. :rolleyes

Fitting a non standard torque would be a more likely culprit.

Another culprit would be, not loosening the caliper side torque arm bolt when adjusting the chain.

Sorry don't get that unfazed, why would you need to do that? If the torque arm is undone but the calliper bolts aren't and you realigned the rear wheel/chain tension the torque arm would still be in the same place. It's all a fixed point.