You didn’t say what the specific objections were, so I can’t respond to that.
My go to enclosure is an indoor/outdoor enclosure made by Orbit for sprinkler controllers. If you search the forum for “Orbit” you will see a few installs. What I like about this box:
Big enough for IoTaWatt, VT and USB and connections.
Has mounting plate inside to screw IoTaWatt to.
Has a UL duplex GFCI inside for the USB power and VT.
Has a lock
Seems to pass the WiFi OK.
You mention multiple IoTaWatt. There is an example of a dual setup here.
The Accu CTs are UR, the VT and USB power are UL, the IoTaWatt is certified to applicable standards by ETL.