Your evap fan is likely to already be vented up and down, sucking air into the center. That's something you can check for, my brother.
If things seem to be stratifying, you may just need to pull boxes and stuff away from the back, top and bottom of the unit so that fan can do it's job.
It's real easy to overstuff a vino. By getting in the habit of not pushing things to the back, it'll avoid filling a box of smokes with the condensate that drips down the back wall.
There needs to be airflow over that condensate, too. It has to get evaporated and sent back to the air and beads.
If you imagine what the airflow looks like after you look at your fan, at the very least it'll help you to properly place the auxilliary fan so you get the results you want.
It's just always better to practice good, informed husbandry than to try to fix troubles that we create, cause they tend to compound until we cause a really big problem.
Mind ya, I'm just going from experience from building lots and lots of these units. I haven't seen yours, and your evap fan may not be working correctly. That might be causing your problem, it may not.
Adding another fan won't hurt anything at all. Just make sure your condensate puddle around the plugged drainhole is getting airflow and your boxes aren't pushed against the back. One of our guys flooded a whole tray of Anejos and ruined most of them by pushing the tray all the way to the back and allowing it to fill with drippage for a long period of time.
That was a very sad day.
Good Luck, my man!!!
