If the work is a "clean room" reverse engineering job, as in: you didn't read the original source to produce your version but rather looked at the input and output and wrote new software that had the same behaviour, the this new software is not a derivative work and you can use whatever license you like.

The easy option is public domain, which effectively is a "this belongs to everyone" thing. There's not much of a practical difference between this or MIT in my understanding.

Another option would be something that preserves the freedoms you attach to the software like the GPL or LGPL if youre feeling less aggressive. These licences compel would-be modifiers to share their changes with everyone else, preventing (for example) companies that want to build their business on top of your work and then charging you for it.

But basically, if you wrote it without referencing the original, it's your work and you can do as you like. If you were referencing the original source though, then that's a derivative work and you may be in violation of the copyright holder's rights.

I’ve got some skepticism alarms going off on this one.

What exactly does “basically reverse engineered some assembly” mean here? Decompiled to C?

And what do you mean by “remake in assembly”? Like, literally writing assembly by hand? Or compiling C source?

I’m not a lawyer, but my guess is that binary-to-binary translation isn’t enough to strip the license, even if you’re making a pit stop in a higher-level language.

Depends on what you want to make of that code i guess. Any license is fine, depends on use case and appliction.