Thanks for posting the sample file.
Alas, MLP can't decipher the file either. So that rules out the following file types (from the MLP help files):
Word Processing
PC
Ami Pro 1.2, 2.0, 3.x
AppleWorks 5.0
ClarisWorks 1.0, 3.0, 4.0, 5.0
DCA/RFT
MS Word DOS through version 6.0
MS Word for Windows 1.x, 2.0, 6.0, 95, 97, 2000, XP 2002
MS Works for Windows 2.0, 3.0, 4.5, 95
Multimate 4.0
Professional Write 2.0
RTF
Text
WordPerfect DOS 5.0, 5.1, 6.0
WordPerfect Windows 6.x, 7.0, 8.0, 9.0, 10, 11
WordPerfect Works 2.0, 2.1
WordStar 5.0, 6.0, 7.0
Mac
AppleWorks 5.0
AppleWorks 6.0 (read only)
ClarisWorks 1.0, 2.x, 3.0, 4.0, 5.0
FrameMaker MIF 3.0
MacWrite II
MacWrite Pro 1.0, 1.5
MS Word 4.0, 5.x, 6.0, 98, 2001, 2003
MS Works 2.0, 3.0, 4.0
Nisus Writer 3.0, 4.0
RTF
Text
WordPerfect 2.x, 3.x
WriteNow 3.0, 4.0 (read only)
AppleWorks (Apple II) 2.1, 3.0, GS
Spreadsheet
PC
AppleWorks 5.0
ClarisWorks 1.0, 3.0, 4.0, 5.0
Excel 2.x, 3.0, 4.0, 5.0, 95, 97, 2000, XP 2002
Lotus 1-2-3 (WK3, WK4, 97, 98, Millennium 9.5)
MS Works for Windows 2.0, 3.0, 4.5, 95
Quattro Pro (DOS) 4.0
Quattro Pro (Windows) 1.0, 5.0, 6.0, 7.0, 8.0
Quattro Pro (Windows) 9.0 (read only)
SYLK (read only)
Mac
AppleWorks 5.0
AppleWorks 6.0 (read only)
ClarisWorks 1.0, 2.x, 3.0, 4.0, 5.0
Excel 2.0, 3.0, 4.0, 5.0, 98, 2001, 2003
MS Works 2.0, 3.0, 4.0
SYLK (read Only)
AppleWorks (Apple II) 2.1, 3.0
Database
PC
ClarisWorks 1.x, 3.x, 4.0
Comma Separated Values (write only)
dBase III, IV (DBF)
FoxBASE/FoxPro
MS Works for Windows 2.0, 3.0, 4.5, 95
Tab Text (write only)
WordPerfect Works 2.0
Mac
ClarisWorks 1.0, 2.x, 3.0, 4.0
Comma Separated Values (write only)
FoxBASE/FoxPro
MS Works 2.0, 3.0, 4.0
Tab Text (write only)
AppleWorks (Apple II) 2.1, 3.0
Graphics Formats
GIF
JPEG
PC Paintbrush.PCX
PICT/PICT 2
TIFF
Windows Bitmap.BMP
Windows Metafile.WMF
WordPerfect.WPG 1.0, 2.0
EPS (translate between Mac and PC formats only)
Compression
Compact Pro (.cpt)
MacBinary
Gzip
StuffIt (.sit)
TAR
Z
Zip
Encoding
BinHex
MIME
uuEncode
--------
File Juicer, another handy tool in cases such as this one, also cannot parse the file. Although FJ also boasts an impressive array of file types that it can recognize, it can't handle this one. And just for the heck of it, I tried feeding the file to GraphicConverter, too, just in case this file might be in some arcane image format. It's not.
Interestingly, the file contains no clear (i.e., human-readable) text at all. Back in the day, most word processors stored most of what you typed in relatively straightforward, clear-text fashion. Even at the hex level, you could make sense of the data stream if you knew what to look for. Here, however, there's not a bit of clear text.
There's also, at the hex level, neither a creator code nor a file type, a classification/file-recognition system that Apple used for many years. Any document produced by an application would automatically be tagged with a creator code and file type, but this sample file has neither one.
It's also not an alias of a file, which would have a unique data signature that could be observed at the hex level.
If I had to guess at this point, I'd say the file is corrupt, compressed, or perhaps encrypted (the latter is unlikely, I would imagine, unless that's quite an astonishing stuffed cabbage recipe!). Post a couple more files, if you want, and I'll poke at those as well with the tools before me.