Hey Guillaume,
Thanks for reaching out!
Our plugins unfortunately do not have any integration with that PDF Voucher plugin. 🙁
Implementing any special features that integrate the plugins may be possible, but would unfortunately require many code customizations to implement. 🙁
So to implement the features you describe, you would have to write that custom code or hire a professional developer to write the code for you. We have a list of great developers here → http://m.tri.be/18k1 (and have no affiliation with any of these folks—they’re simply some well-respected names in the community that we’ve compiled to share in situations like this one).
Sorry to disappoint!
Sincerely,
George