There is no LTE band 13 or band 4 and no way to tell if it is capable of VoLTE or not. The A70 isn't compatible with the Verizon Wireless network. The link to the A80 doesn't list the LTE frequencies to know if it is compatible or not. If it has the same LTE frequencies as the A70 version then it is likely to not be compatible.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.