There were two Hatchet Faces?
If that were actually the case, they’d be up to ten people even as they’re looking for someone to fill the ninth slot of the Slaughterhouse Nine (Siberian, Jack Slash, Burnscar, Mannequin, Shatterbird, Crawler, Cherish, Bonesaw, Hatchet Face and Hatchet Face).
Then again, Hatchet Face appear not to be counted after whatever Cherish did.
Then the first one exploded into a cloud of white dust and blood spatters, momentarily filling the room. Amy could hear Bonesaw’s giggling, felt her heart sink.
This reminds me of Bakuda’s decoy gangster bombs, except these aren’t holographic.
The white dust and apparent teleportation/cloning also remind me of Oni Lee, who last we knew was being taken back to the Slaughterhouse Nine, though that might’ve happened after this. But if it didn’t, it’s quite plausible that Bonesaw studied him and in some way adapted his power into some of her technology, much like how one of Bakuda’s bombs was based on Vista’s power but with the Manton effect overridden.
“Get it? You figure out what I did? Turn around, Hack Job.”
Hmm. Or did she modify Oni himself to look like Hatchet Face?
Amy had figured it out, but Bonesaw’s creation demonstrated anyways. He turned his back to Amy, and she saw what looked like a tumorous growth on the back of his head, shoulders and arms.
Oh jeez.
Except the growth had a face, vaguely Asian in features, and the lumps inside the growth each roughly corresponded with organs and skeletal structure.

Hatchet Face is still around, Burnscar said, “sort of”.
Bonesaw fused them. She fused too broken men together.
And now they have one body and probably both powers, though Oni’s power doesn’t work flawlessly with Hatchet Face’s body – thus the bloodspray accompanying the usual white dust.
As for any similar incompatibilities the other way: If Hatchet Face’s anti-power field didn’t allow picking and choosing targets (though I suspect it did), maybe Hack Job’s teleportation doesn’t work while the anti-power field is up.
I thought Hack Job was just a disrespectful nickname Bonesaw had for Hatchet Face, but it makes sense to give this fusion its own name, and it seems like an appropriate one.
The jaw of the figure that was attached to the back of Hatchet Face’s body was working open and closed like a fish gasping for air. The stitches were still fresh.
So while this does tell us that Interludes 11a and 11h take place after 11b (and probably before 11c), it seems it wasn’t too long after. She’s just finished this affront to nature.