MP3 export success and fail

Recently I uploaded a demo of Symphonic Sounds font with synth settings as follows:
Dynamics: CC constant CC 11 non-expr

Zita 1 RT60 Mid at 2.8 Eq1 and Eq2 at 1:30 (o'clock) mix 1:00
Effect B none

It came out fine. https://musescore.com/user/29586932/scores/6696002

Another demo could not export with those same settings, so I reverted EQ 1 and 2 back to 12:00 (o'clock)
It sounded okay, but not as realistic.

https://musescore.com/user/29586932/scores/6699946

I do not understand all this, but have a feeling it has to do with the font.

joe