As you'll see, all commands after 0xD5 are missing from that document, not only warp8 (0xE0). Even though, it could very well be that those commands really don't exist in Fire Red. Looking at the command table in the ROM, I see that they point to RAM addresses (0x020370cc in the case of 0xE0). It could be that those addresses were filled with actual commands, but I doubt it - I'd have to check with a debugger.