Chain came off did some damage to crankcase, leaking oil

Chain came off when I was riding and left me stuck on the side of the road. Noticed it was leaking oil, but couldn't tell from where. Was hoping it was just the countershaft seal, but after cleaning everything up and installing the new seal its still leaking.

Short video -  www(dot)youtube(dot)com/shorts/lNsTksdwQ00 <-this site wont let me post a link and the youtube video insert button isn't working.

As you can see from the pics and video, there is a gouge taken out of the crank case from the chain.
Am I totally ruined here? How bad is it? I can't afford to get a new crank case.  Is it possible to weld it or use something like JB weld?
Would appreciate any responses as I want to get riding ASAP.  

I would clean it real good (twice!) then rough it up with course sandpaper and try LB Weld. Not much effort to give it a try. JB can provide miracles at times.

Did you have a master clip type chain link? or a rivet type?

I only ask because I was about to install an aftermarket chain with master clip type