It's not just a "Y" sound. There's a "J" sound and then a "Y" sound together in a consonant cluster. /dʒuniər/

Hi John, I'm Canadian and don't hear the 'y' sound Jonathan JonathN describes. My pronunciation follows the American pattern and in our countries "J" is never pronounced like a "Y." I didn't listen to the link but in many European languages such as Spanish and German the J has a Y sound. Try this link for examples of native English pronunciation. Note that at the top of the screen you can choose the accent you want to listen to. www.youglish.com Cheers

A standard "J."

The man's /dʒ/ was just a little softer than normal, more like a soft /ʒ/. This may have been a blending of the /dʒ/ with the final /z/ in Carl's. This is *not* a reduction that you'll hear often, except in unusually fast (or drunken) speech. In this video, it seems to be just a random glitch. Substituting /j/ for /dʒ/ is typical of most Hispanic accents, and the video was filmed near Mexico, and the speaker has spent time in Mexico, but his accent sounds like native US English to me, so that's probably not a factor.

The first syllable of JUNIOR should sound exactly like the month JUNE. The Y sound is the 2nd syllable.