Betina is an alternate spelling of Bettina (Hebrew): nickname of Elizabeth. With the alternate spelling of Bettina in mind, I would think the syllables would be: bet-i-na, so you should not use the "be" lower groupsign.
Bezalei is not in the dictionary, but I found a French pronunciation at howtopronounce.com that sounded like the syllables are: be-za-lei, so you could use the "be" lower sign. However, are you sure of the spelling? Could the word be "bezalel" and pronounced as be-za-lel? In either case, I think the "be" lower groupsign could be used.
Bengalia is not in the dictionary and unknown to howtoprounce.com. Again, could the spelling be "bengali" and pronounced ben-ga-li? I think in either case, "be" is not the entire first syllable and the lower groupsign should not be used.
Belize and Belarus are in the dictionary with "be" as the complete first syllable, so you should use the "be" groupsign in both names.