mac,well all 4 batteries unlikely bad ,power is especially critical in these cars today ,I've heard talk here "get factory OEM alternators , not the BIG-3 cheap w/chinese parts inside remanufacured's"
My Guess is the 'Zone alternator is 1) intermittant 2) shows steady ,OK power ONLY at lower test levels@+rpm's,( in "stopped car"@Lo rpm's it dies -right?) , or OK like when cold -- BUT IS BASICALLY BAD. Couple reasons Nissan didn't find = 1) they simply didn't find(the intermittant) 2) Nissan charged you right?
THEY DON'T CARE how often YOU COME BACK! 3) And NOW they know of the 'ZONEY part that they can "Milk " you for ,for so many times they think your good for - when they WILL FINALLY simply put in the better quality Nissan "Genuine -part".
Cost to you this way ......$$1090+ ?? total ,unfortunately , this is what can be called "De Rigueur" for more reasons than you think.