Hi,
That is a very large jump of version, I suspect you may have a problem in the actual search configuration instead. 4.21.3 is like 30 releases behind 4.24.2, so check the settings, save the options again to refresh the database and try if the regular search gives any results.
If not, you should create a new search instance just to make sure the data is not corrupted.
In your snippet the $search_args_array argument is also likely a source of a problem, as it is not apparent what it contains. Try without that argument to see if it changes anything.