Chaos at its maximum

Also im currently in the process of designing a language for a species with no voice box, lips, teeth, or nose (meaning no voiced sounds, no vowels, no dental/labiodental sounds, no bilabial sounds, and no nasal sounds)

Is their lack of a tongue the reason why the vowel inventory has no front and back vowels?

I guess so

Beltonia is that not that what causes back vowels?

I was only asking because I don't know.