So there must be other data sources used. As it does have airfields displayed correctly that don’t have a 4 letter ICAO code (like the “DOP” airfield from the Aero Club Mendoza that you had also mentioned in the other post). However there seem to be other data sources that provide made up airport codes.
When looking at the local airfields in the FS2024 EFB I have noticed more incorrect 4 letter codes (SAxx):
Besides the wrong SATP already mentioned there are a couple of other ones that caught my eye:
SARD: This airfield does not have a 4 letter code. The airfield is a private airfield from AEROTEC with local 3 letter code “RAE”
SARK: Also does not have a 4 letter code in real life. It is the public airfield of the Aero Club Rivadavia and has a local 3 letter code: RVD
It almost looks like that there is a data source used somewhere that provides these made up 4 letter codes for airfields that only have local 3 letter codes.
I just picked those as an example. There are a bunch of other codes in the screenshot that do not exist. Like the 5 letter codes that start with SA or the SAHA in the upper right corner.