How would you fix this?

[GRADS]

Another vote for a nut-sert. It's basically a threaded pop rivet. Looks like sheet metal screws were used the first time, and then JB Weld to hold it with oversized screws the subsequent times it failed. A nut-sert should be a permanent fix.

Or take it somewhere and have studs TIG welded into the holes and use a nut to hold the bracket on.

I've never heard of a nut-sert....looks like I'm going to have to fire up Google.