Here's my way of migrating xen vm's to pve hosts, I've done a few hundred so far and have had very few issues.
Download and prepare xen-to-pve script
apt-get install git
cd /tmp
git clone https://github.com/guestisp/xen-to-pve.git
chmod +x /xen-to-pve/xva-conv.sh
Make sure you have http access...