It took a while but I figured out a new route! Although it's quite hard to actually pull off, as it seems there's RNG involved with how the guards behave. It's not a perfect run, in fact it's my first completion with the new route, so a perfect one could probably at least get sub 50s. And even then maybe there's other routes that are more optimal. But it's a good step in the right direction in terms of optimizations!