Rivited wheels (outside rim to center) were very common at one time. They are very safe and present no issues in that arena.
A tube is one way to make that repair or an adhesive would be another as liong as the adhesive is not applied any where near the flange of the rin where the tubeless tire seats and the adhesive is up for the extereme heat and pressure of teh job.
On a different wheel for a Toyota I made this type of repair for a pin hole leak in a cast metal wheel. The amount of adhesive used was very small and I had to do the repair twice because I did not let the adhesive cure. The tire was balanced after the repair and no one can see the repair since it is on the inside of the rim.
1966 Mercury Park Lane 4 DR Breezeway 410 4V, C-6, 2.80 - Streamless.
1966 Lincoln 4 door Convertible 462 4V 1971 Ford LTD Convertible 429 4V Phoenix ~ Yeah it's hot however it's a dry heat!