At this point, both VMs have same network adapter name, eno16777736, but MAC address is different:
vm1.example.com = MAC 00 :0C :29 :81 :CD :CC
vm2.example.com = MAC 00 :0C :29 :9C :EE :6C

The vm1 and vm2 IPs are 192.168.0.43 and 192.168.0.43 44.
When pinging broadcast IP, 192.168.0.255, from vm2 (192.168.0.44), I get response from 192.168.0.XXX where XXX is not 43 or 44.

Why am I not getting a response back from 192.168.0.43 (vm1) if I ping from 192.168.0.44 (vm2)?

How do I know which VM is responding since they both have same
first three digits, "192.168.0.", and thus their broadcast IPs are same also?

Thank you.

The response should be the IP address of the device as far as I know. I don't know how your network or your VMs are configured but check to see if /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts is enabled i.e 1. If so and all of mine computers seem to be a 1 so they do not respond. I assume you are pinging using the bolow command.

ping -b 192.168.0.255