Holy hell. You need a new subframe. There's no alternative. No welder is fixing that! Do not dare drive that car as it is, you're lucky you didn't have an accident. You weren't kidding when you said the car is not safe.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]