I have played Part 1 probably 30 times and that staff has always been there.Try this, download and install Grayface V1.8 patch. Among the many things it fixes is the "chest" fix. When a chest is loaded by the program sometimes items that were suposed to go into that chest are not there because they wouldn't fit. This was true in the original game and TCC both. Grey's patch fixes that problem and if you open a chest a second time, the items that didn't fit the first time are now there.
The patch contains MOK's latest patch (V1.3) and also Angel's patch as well as the official upgrades up to and including V1.2. The patch does not care if you already have those patches and/or upgrades installed, it just overwrites them.
I personally wouldn't play MM6 again without that patch installed.