I am agreeing with
@North Idaho Wolfman on the “I don’t see a crack”! I also thought what
@TheOldHokie thinks is suspected crack but that just looks like pooled oil with light reflecting off it now.
I don’t think the size of the bolts and the (probably aluminum) material they thread into have the strength to do damage to that hunk of steel, but I concede that anything is possible.
I personally don’t see any reason why there would be a leak on the face of that joint, so I have no idea what is going on.
@Smokey160 - please clean that part up a bit to remove the oil since it reflects the light oddly in pictures. I would use Berryman B12 or a non-chlorinated brake parts cleaner in a spray can to blast it clean. You should remove the o-ring first or it will probably get lost. Then take another picture of the part after it dries without the o-ring and another with the o-ring. I guess if you have some third hand available use a sharp pencil point or something similar to point to the suspected crack to help us see what you are looking at.