The error message is not very helpful unfortunately.
You are missing the required library LASzip on your system as well as the laszip.exe tool.
For Windows you can get the LASzip DLL file from the archive the LAStools project provides at https://lastools.github.io/download/LAStools.zip
You can find it in LAStools/LASzip/dll/ in said archive.
For quick ...
I think your json is being interpreted as a string rather than as a json object.
Try importing the json library (part of the standard Python library) and then loading the string as a json object. For example:
json_string = """
You can download data in LAZ-format which you can covert to las from Lantmäteriet (~The Swedish National Land Survey) from this link. Create account and download via ftp. The lidar data is in folder "Laserdata_Skog". Coverage as of 2019-08-07:
Green-ready to download
Yellow-quality Control in progress
Red-scan in progress
I constructed a 24 billion point lidar point cloud web service available with color information that might be suitable for this task. It is available in Entwine Point Tile format on AWS courtesy of Bohannan Huston and the City of Hobbs, NM. You can view it in Potree at https://hobbslidar.com.
The EPT resource link is https://na-c.entwine.io/coh/ept.json. ...
After converting the LAS Dataset to a point feature class, then add x, y and z coordinates to the TOC with Add Geometry Attributes tool:
Adds new attribute fields to the input features representing the spatial or geometric characteristics and location of each feature, such as length or area and x-, y-, z-, and m-coordinates.
Another option is to use the ...
There are things you can do to the files before you compress them to make the LAZ compression more efficient. Sort them based on GPSTime if you have that attribute. Sort them along a space-filling curve if you don’t.
Zero out attributes you don’t need. If you have color information in raster data elsewhere, it will be much more efficient to compress them ...
To answer your first question: No. The tools and supporting documentation over at LASzip.org covers the details. A lossless compression is absolutely critical with LAS data and this group has ASPRS official support afaik.
To answer your second question: No. Though you really ought to have tried that yourself. Also, 7zip is no improvement over WinZip, etc.