Thanks for that information Sean. I've done some research of my own and am happy to share. Hoping that others may have made the purchase and can confirm my comments below. Or can give feedback on whether the product will cut it in real life.
So the research target battery, hand held smoke machines that allow easy access and investigation of air leakage without need for power and associate chord trailing along.
At about half the price of the Tiny CX I've identified this one as an possible contender.
At $700 it comes with an extensive Kit of smoke diffusion devices and also a battery powered fan than can spray the fog around. It does not come with the rechargeable batteries. A set and spare set will set you back around $180, but at least if you run out of power on site, you can change over the batteries quick and easy. The best video review I've found on line is here:

An alternative that is cheaper again and appears to perform like the Tiny CX is the MicroFogger 3. The issue I have with this is the batteries are fixed internally and can not be changed out. Recharge time is 6 hours. 20minutes continuous usage times, means the fog will run out before the battery, but how long will it give you on site? Best video I could find.
For a Kit of parts (including fog tank size extender, wand and remote) it can delivered to SA $200+ Total purchase for $580 with a remote control $530 without. Including case. I think this has real potential if you ban handle the battery dying on site. Or by 2 and have one spare I guess for the price of a tiny FX.
The JPv Minifogger is only $650. From the UK the catch is $470+ for shipping. Making it nearer $1200. It does not feature the smoke management parts or distribution fan on the Smoke Genie, seems have similar output though.
The JPv MINI FOGGER™ is the most cutting edge machine available to the entertainment industry. The JPv MINI FOGGER'S™ advanced vapor technology enables this small device to produce great fog tha
rogergeorge.com
This website compares (to some degree) the MicroFogger 2 (similar but less display features to the 3)
https://vosentech.com/index.php/2020/04/28/microfogger-vs-its-competitors/
Pea soup make battery powered fogger and a large 400W fogger. Pricing for the small unit (Micro) similar to the Mini CX, at about $1200 AUS dollars, but this without shipping. That could easily be another $300 - $600.
Pea Soup smoke and fog machines.
www.pea-soup.com
Wasteland Industries have some interesting small scale machines in development, but video show exposed wires and a corded power supply making me think not suitable for a build site. Photographic studio, yep! $160 delivered. Sean be interesting to see if you think its better than your modified vaper. Issue would be output of smoke and potentially battery life, unsure but powered by a USB powerbank.
At the moment I'm leaning toward the Smoke Genier or Minifogger 3
Hope this is interesting for people.