Plume of Pursuit with Blade Vortex

Plume of Pursuit with "BV link with spell echo" will always no crit.

However, if I use "Blade Blast link mine support" to detonate the first blade vortex,it will become always crit.

I think there is something wrong.
Please fix it.

Viedo:
always crit at 2:45

https://www.youtube.com/watch?v=ZpyO8zEU6Sk&feature=youtu.be&ab_channel=%E8%B3%B4%E9%98%BF%E5%A5%87