I believe the easiest way to judge this is to look at the...

I believe the easiest way to judge this is to look at the product itself. Let's use the US product that they have been talking about that has recently been put on the EPA List- N (This is the list of Disinfectants that kill Covid-19) it has the ingredients listed as;

ACTIVE INGREDIENTS:
3-(trimethoxysilyl)propyl dimethyl octadecyl ammonium chloride ......................... 0.50%
Alkyl (67% C12, 25% C14, 7% C16, 1% C18) dimethyl benzyl ammonium chloride.. 0.50%
Hydrogen peroxide ……………………………………………………………………………………………… 0.50%
INERT INGREDIENTS …………………………………………………………………………………………… 98.50%
TOTAL ………………………………………………………………………………………………………………..100.0%

The latter two ingredients are very common and well used across numerous similar products and the Trimethoxy product is just Dow Corning 5772 (Google it).
None of these products (or any combination of) are approved in the US with a label giving "longevity"claims such as "lasts for 24 hours or 30 days etc in relation to public health such as bacteria or viruses that cause illness and the List-N approval doesn't allow such claims either. However Trimethoxy as an active has been approved as a treatment for mould and odour cause bacteria (what the EPA call nuisance mould or bacteria) and the label is allowed to say that some surfaces only need recoating every 60 to ninety days, but this is not for public health issues.
So in summary you have a product with active ingredients that aren't unique, nor were they invented by Zoono. These ingredients can kill pathogens that cause illness (this is well known as these are common ingredients used in many such preparations), but in the US the EPA will not allow claims of residual activity claim to be made because these ingredients don't meet the standard required to make such claims. The exception is residual claims can be made regarding nuisance bacteria but not viruses or any public health related issues.

In fact if you look at the EPA enforcement action taken against Zoono in 2022 it states " Zoono Microbe Shield sprays were advertised and offered for sale on various websites, including Zoonousa.com, Zoono.com and Amazon websites. EPA’s review of the product’s labeling revealed that the companies had each sold the product with public health claims that substantially differed from statements submitted in connection with its registration with EPA and with other false and misleading claims, which is illegal under FIFRA. Numerous online purchases were made by individual consumers and institutions – such as community centers – located in areas with potential environmental justice concerns.These violations raised particularly serious concerns as Zoono Microbe Shield labeling, particularly its online advertising, appeared to have diverged from allowable claims during the pandemic, increasing the likelihood that unsuspecting consumers purchased the Zoono Microbe Shield spray with the false expectations that it could be used as a sanitizer or disinfectant to prevent SARS-CoV-2, the virus that causes COVID-19, as well as other germs, viruses and pathogens. Claims allowed for Zoono Microbe Shield as part of its registration include effectiveness against odor causing bacteria, bacteria which cause staining and discoloration, fungi and algae as a static agent. Significantly, approved uses allowed on Zoono Microbe Shield labeling do not include use as a disinfectant or sanitizer or any public."

So to gain List-N classification Zoono had to change the formula from one that only contained 3-(trimethoxysilyl)propyl dimethyl octadecyl ammonium chloride as an active to a formula with Alkyl dimethyl benzyl ammonium chloride and Hydrogen peroxide, that is because those two ingredients do kill viruses and bacteria but this formula doesn’t allow the longevity claims.The conclusion to me is that there is nothing unique or proprietary about Zoono products, in fact if you do your research, you will see they aren’t even manufactured by Zoono, they were made by a third party chemical manufacturer in South Carolina that makes similar products for other companies. The first Zoono EPA registrations were a sub registration of another companies’ product. There is not and was never a “Zoono molecule”, the ingredient they are making these claims about is 3-(trimethoxysilyl)propyl dimethyl octadecyl ammonium chloride and as I said this is just Dow Corning 5772.Zoono is just one of many similar products that had a huge lift in sales due to a global pandemic and now that the pandemic is over so is Zoono, and a good look into what it actually is tells you that they got very lucky to have even ridden that wave as some of the product claims they made were not inline with the approvals. I am sure the NZ CC prosecution will yield some interesting information.