I suppose it's possible....as is anything. I am a bit concerned about just sticking a bolt in it and hoping that the silicone actually seals it up again. Once the cured silicone is ripped apart, it's no good. You can try it though!
I'll send you a bolt (you may have to send me your address again
) but I can ship it Monday.
On edit:
The oil that I'm noticing in the pictures is pretty common of loose clamps on the orange hoses from the "y" into the plenum. I've fixed a couple "rear main seal leaks" just by tightening those clamps.