Multiple screws snapped inside the block

How cooked am I? For context I bought my kz650 from an idiot teenager that knew zero about bikes. It was also junkyard quality but I took on the challenge of bringing it back. It's almost done now, 2+ years later and after buying a replacement sprocket cover I now know why the original was lost to time. They snapped 4 of the 5 screws that holds the cover on into the crankcase. I've tried alot to remove them with no luck. What do I do? I'd ride with no cover but you need the cover to actuate the clutch plus safety or whatever but mainly the clutch. I'm attaching photos, if anyone has any suggestions or ideas I'm all ears. And no a new engine, crankcase, or anything in between is not on the table. I've spent well past what the bike is worth at this point.

Personally I would drill out and tap new threads,
Rich.
 

I've tried but all the snaps arent clean. They are at weird angles that make the drill bit wander. Also the original screws are hard alloy that apparently dulls 75% of drill bits.

That's what they make cobalt drill bits for.

Use a center punch in the middle of the busted screw and make a dimple.  Drill a small hole in the screw, and work the drill bit sideways as needed until the hole is dead center.  Then move up to the next size drill.  Using left hand drill bits works well.  When the old screw is just a shell, it will likely spin out when drilling.