Okay, I see what happened. I used "darkhalfj.smc" to generate my patch and the checksum information posted in the patching info, but only just found darkhalfj_unmod.smc in my project folder. Whoops! The latter does indeed match the MD5/CRC32 info you've posted. I'll update the patching info accordingly.
The differences between the two ROMs however are extremely minimal. I used Hex Workshop's compare function, and the only thing that's changed between the two is that there are a series of pointers to the original text which had their value increased by one. The patch actually leaves the entirety of the original text structure intact, so this difference does not matter in the slightest; however, I can verify that the CRC32 for the patched ROM is 18877841 and that the MD5 is 1095474903C14921A17EDB56A2D58870. In fact, these bytes are unchanged in the English ROM so the patch likely changes them *back*. (In other words, the patch changes them from what they are now to... what they are now.)
Apologies for the confusion.