Yes, i have same problem.
This is since last releases.
With a light code change, you solve the problem
in JOOMLAROOT/administrator/components/com_virtuemart/helpers/vmjsapi.php
after
Virtuemart.updateChosenDropdownLayout = function() {
add
if( typeof jQuery.chosen === "undefined") return;
It's not heavy tested, but the problem is most case because all Virtuemart changes and template, it's sometime a nightmare when you need to customize the javascripts for a shop