our main question we are trying to figure out is what the legality of this packing / unpacking software is. We have been trying to see what Hikvision's EULA / agreement is but the one on their firmware page is either incomplete or unclear
There are multiple firmware download sources provided by Hikvision.
The most comprehensive source is the Hikvision Europe site, which has no EULA in the
downloads section.
The Hikvision China site is in, well, Chinese.
To be honest, in my view a more interesting, admittedly linked, topic would be Hikvision's actions that deliberately damage the operation of the products their customers have purchased.
Hikvision freely publish firmware updates for IPCs and NVRs.
Many customers will be used to doing updates to products that have 'deferred design' capabilities by the use of firmware and software.
The normal expectation is that the updates provide bug fixes, extra functionality, and, topically, security fixes and improvements.
What they don't expect is that Hikvision incorporate deliberate changes such as 'language mismatch' code that renders the devices inoperable in the way they are intended to be used.
Those actions are in my view certainly immoral, and in some jurisdictions would fall foul of Trading Standards and Competition legislation, given their underlying anti-competitive purpose.