Microsoft did underwater datacenter and had a lot of success with it. Yes, they had hardware failure but it stayed underwater for years before they pulled it from service.
https://news.microsoft.com/source/features/sustainability/project-natick-underwater-datacenter/
I wouldn’t have done UDM route if it wasn’t for NVR built in. Read up on the other offering around November last year. Number of cameras I plan to have down the road didn’t work with the other units.
Is your CPU on the Nas maxed out?
Have you tried running iperf test to verify network is capable of delivering the expected speed?
Iperf on qnap
https://www.qnap.com/en-us/how-to/faq/article/how-do-i-install-iperf3-in-qts-and-quts-hero
What disk is in the external USB?
What drives do you...
What version of ESXi and CPU do you have in your ESXi host?
https://knowledge.broadcom.com/external/article/303440/understanding-exception-13-and-exception.html
https://williamlam.com/2023/04/esxi-psod-due-to-gp-exception-13-in-world-with-intel-13th-generation-cpu.html
I used this site below for dynamic DNS with my own domain years ago. Buying a cheap domain and updating it to below site sounds cheaper than alternatives presented above.
https://freedns.afraid.org/pricing/
I use BackBlaze B2 Cloud as target for a Synology NAS. NAs holds pictures and backup of Desktop PC. Been using it since January without issues.
I compared Backblaze with google, onedrive, and synology cloud, but backblaze came out cheaper for my needs (500GB).
Want to go the camera route and connect back to another building wifi. You can take a look at a point to point setup like this. You'll still need a switch and wifi device in the shed for the camera to connect to an access point...