In George R.R. Martin’s A Song of Ice and Fire series, there is a somewhat exotic character called Jalabhar Xho:

JALABHAR XHO, an exile prince from the Summer Isles

I’m not sure how to pronounce this character’s last name: “Xho”.

A few reasonable guesses for the ⟨xh⟩ digraph include:
/k/, /ks/, /ksh/, /ʃ/, /gz/, /ʒ/, /dʒ/, /h/, /x/, /χ/, /kǁʰ/, /ᵏǁʰ/, ∅

But, as I’m not sure which language(s) inspired the Summer Tongue, it’s unclear which (if any) of these guesses are correct.

Are there any clues as to how George intended this name to be pronounced?