Thank you for your question!
You already summarized a few of the important changes of the "Fachkräftezuwanderungsgesetz"(skilled labor immigration law) that has been passed on December 19.
Here are two English articles that might help as well:
The Guardian: "Germany passes immigration law to lure non-EU skilled workers"
DW: "Germany's new immigration laws open door for skilled labor"
As far as I understand it, the part of the law called "Beschäftigungsduldung" applies to people who have not been granted a legal status as a refugee in Germany or who's asylum claims have been denied, but who received a "Duldung" based on necessary humanitarian, personal or legal reasons. Duldung = temporary suspension of deportation.
That means: Said people can receive a "Beschäftigungsduldung", which lasts for 30 months, if they
- have had a Duldung for 12 months
- have been working for 18 months, at least 35 hours per week (also paying social security),
- speak German well
- and have been able to cover their living costs for the previous 12 months, plus will cover them in the future
(This is from the Bundesministerium für Arbeit und Soziales/ BMAS, a German source)
I hope I was able to explain the core changes, the sources can be helpful in understanding the law too.
Please don't hesitate to reach out to us again if you have any more questions!
All the best,