Masters in Germany in Engineering
Why did you not explain your circumstances? I understand that you want to avoid the topic and do not want to justify your bad grades with something personal. But in your case, especially considering depression, I think that mentioning the reason for your low grades should rather help than damage your case. The key is to be honest, reflect on your past and give them a reason to let you in, e.g. you have overcome your depression and want to start over in your masters.

I don't think work experience matters much to be honest. Engineering in german universities is rather on the theoretical side as far as I can tell.