Hello
Please try add IP addresses in C:\Windows\System32\drivers\etc\hosts file for vCenter and ESX host.
Don't know why but converter always try migrate to first ESX from cluster, even when I chosen ESX02.mydomain.com, into logs visible was information that he cannot resolve ESX01.mydomain.com
C:\ProgramData\VMware\VMware vCenter Converter Standalone\logs\vmware-converter-worker-1.txt
I also P2V 2008R2 with converter v 6.2.0, source 2008R2 server out of domain.
hosts file:
192.168.10.10 vcenter.mydomain.com
192.168.10.11 ESX01.mydomain.com
I also installed SSL certificates visible during converter warning message 'Converter Security Warning'
I've chosen 'View Certificate' instead 'Ignore' option and Install
In my case above actions solve problem