Goddammit. You / your friend (1) didn't use the guide (at least not from the beginning), (2) have no backup and (3) apparently like to use deprecated tools (some of these caused by each other). You even managed to use an outdated version of SafeA9lhInstaller for the second install, which surprises me as you started using the guide at this point. What you got here is very near the worst case scenario. You also actually made it worse, cause when you got the console it still was in a perfectly saveable state, now I'm not so sure anymore -_-. Okay, what to do about this mess...
With all that happened to that 3DS so far (old tools and stuff), it is not in a defined state. If it were just two proper A9LH installs, no problem. That would still lead to a working A9LH installation. I fear there is something else wrong with this, though.
Try this,
@PudimEXTREMI. Empty SD card, only arm9loaderhax.bin on it. Get
GodMode9 from here, rename the GodMode9.bin from the archive to arm9loaderhax.bin, put it on the SD card root. Try to boot with this SD card. If it doesn't, rename arm9loaderhax.bin to arm9loaderhax_si.bin, try again. If it still doesn't work, maybe try another SD card and repeat (try both names). Follow these instructions exactly. After you tried this, let us know if you had success.
EDIT: Also make sure you use a SD card that actually works. Maybe a known working one from another console or the one that came with this one? It has to be formatted as FAT32.
If nothing of that leads to GodMode9, you won't be able to save this console. In that case, it might be broken beyound repair, or it might be saveable via hours of work and a hardmod. You'd need to find someone who'd do that for you.