It looks as though your 'pxelinux.0' file is located in /share/Public/tftpboot yet your actual TFTP Server logical root is /share/Public...this is a problem, either relocate all your files into /share/Public or alter the TFTP Server configuration to point to /share/Public/tftpboot/...
That said the details you've provided suggest no connection at all is being made with the TFTP Server, so unless the error message is a little mis-directing I don't think that correcting the above will solve all your problems but its a start.
Can you test using a acutal PC rather than a vm...sometimes how the vm connects through to the NIC can cause issues perhaps? Also can you validate that the dhcp-boot option is being passed correctly...use something like iPXE, boot up from usb and at the commend prompt issue a 'dhcp' and then 'config'...the list returned will show you whether the TFTP IP and boot filename were recevied properly.
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