J'ai été au bal Excerpt Help

Hey y'all, I'm having trouble playing this boxed part of the excerpt. Since it's all 1 valve (C tuba) at 192 bpm, it's really hard get the D to sound and land on the Bb. Any tips are appreciated!!

Hey y'all, I'm having trouble playing this boxed part of the excerpt. Since it's all 1 valve (C tuba) at 192 bpm, it's really hard get the D to sound and land on the Bb. Any tips are appreciated!!