The error message is "cannot find initrd config file /mnt/p2v-src-root/etc/modules.conf in target"
/mnt/p2v-src-rooot is the mount point where the source file system is mounted in the helper VM. It seems you don't have /etc/modules.conf on the source machine. Find out which file has the modules configuration, copy it to /etc/modules.conf and try the conversion again.
HTH
Plamen