Everyone that has not received a voucher and thinks they should have, email "educations-service@juniper.net" to let them kno. I did this today an Lawrence responded. I got my voucher shortly after that.
There seems to have been a flaw in when they ran the report to see who had completed the requirements. For me, their system did not show me as having completed the practice test, even though I had. They were able to go in and verify that I had completed it and sent me the voucher code via E-mail.