Since it is near the rear of the block....did the shop consider drilling and reaming the passage oversize, then pressing a thin wall sleeve in place to reform the oil passage in the section that is blown out??
Sealed in with a Loctite sealer along with a .0005"-.002" press-fit.
This would save the 4-bolt block and all the machine work already performed.
I don't know the exact size without being there to see the situation, but something like 1/2" or 9/16" x .015-.030" wall tube...could be brass or steel.
Wicks Aircraft Supply has 9/16" x .035" wall chrome moly at $7.00 a foot. 1/2" x .028" wall at $5.23 a foot
I've seen spun main bearing webs fixed by Lock-Stitch pinning 1/2 moon sections of small engine cylinder sleeve into overbored main saddles, and the whole thing line bored and honed to save a 4-bolt L88 block.....an oil galley sleeve is cake walk compared to that.
I should have mentioned earlier, block would have to pass a crack test in the broken area first.
Not much different than drilling and reaming for a replacement valve guide....if the hole is short enough a 1/2 diameter replacement bronze valve guide blank could even be used, then drilled to close to original galley ID after it is pressed in place. The style of blank used to put bronze guides on old stock iron heads like SBC camel hump or BBC 049's.