Just small recommendation to change the library.
Concerning timestamp to string conversion:
The current format string "%Y-%m-%dT%H:%M:%S%3uZ" in "Variant to Json Text.vi" is dependent on localization. On my german windows this leads a to timestamp according to Iso 8601 of "2019-07-26T14:17:20,053Z". Notice the comma for the fractional seconds. According to the Iso both, comma and point, is valid (Apparently, the Iso even recommends the comma https://en.wikipedia.org/wiki/ISO_8601#cite_note-25). However, it seems that the point is used more regularly in practice, for example in .net (see Json.net package). So I would suggest to change the format like this: "%Y-%m-%dT%H:%M:%S%.;%3uZ". This ensures using the point instead of comma., hence the format is independent of your local setting.