The concept of redundancy is different in NL with completely different requirements and legislation as you would probably appreciate. It is fundamentally based around Termination and Settlement Agreement with the documentation being rather specific. If you want my advice unless you are super confident I'd simply go to a law firm and ask them to do everything. They will do the calculations, letters and submit the relevant documentation to the department of labor before any notification (a legal requirement) all for you and will cost about 5000 EUR a drop in the ocean compared to a ET Tribunal Proceedings cost.