I know whos high dollar racin engines are full of goo now...with holes in the block.......

Some of the new liquid adhesives are amazing,I would think anything along that line would work well,using the tactics listed above.
I would tap the hole and then use the plug with red loctite and then either use the resin or some sort of good block fill.

Some of the resins/liquid steel and adhesives will probably outlast the rest of the engine..........
If that stuff is anywhere near like body panel adhesive ,its gunna do the trick,for along time.