There are a couple of alternative procedures, depending on whether you want to keep any files on the hard disk or not.
At this point, I will assume that you do not wish to erase the whole disk, if possible (may become necessary anyway, if the logical structure is severely damaged).
When you have started from the floppy, you should see a hard disk icon ("Inside the Machine"?). If not, post back. Locate the existing System Folder on that hard disk. Click on the name and rename that System Folder (call it OLD System Folder). Move the System suitcase out of OLD System Folder (place the suitcase inside any other folder on the hard disk; remember where). Finally, locate the System Folder on the Network Access floppy, and drag-copy this System Folder onto the hard disk.
You should now have both an OLD System Folder (which does not contain a System suitcase) and a System Folder (that is, a temporary one copied from the floppy) on the hard disk. Choose Restart from the Special menu. The computer should eject the floppy and start from the hard disk.
Download HFVExplorer (under the "New battery on Performa 475 - no boot" topic in this section, AppleIIFreak has indicated where to find the program; otherwise try a Google search). Install the utility on the PC.
Disk First Aid
7.2.2 onto the PC (keep the .bin file as it is).
Locate a Mac-formatted 1.4 MB HD floppy (preferably empty, or at least with approx. 100K free space).
You may have to temporarily unload any anti-virus software. Double-click on the HFVExplorer icon in order to launch this PC program. Insert the Mac floppy. Refresh by pressing F5 on the PC keyboard. The Mac floppy will appear as a white icon (top) in the left HFVExplorer pane.
Locate the Disk
7.2.2.sea.bin file (possibly a truncated name) on the PC. For example, if the file is directly at the C: level, select the (yellow) C:\ icon in the left HFVExplorer pane and the file will appear in the right window. Drag the file from the right pane onto the (white) Mac floppy icon in the left pane. A Select copy mode dialogue box will appear. Select "MacBinary2" from the list, then click OK. You will notice activity from the floppy drive (the program does not provide a progress report, so keep an eye on the floppy drive indicator light). When finished, immediately eject the floppy (which should contain a self-expanding archive, Disk First Aid 7.2.2.sea).
Move to the IIvx. Insert the Mac floppy and drag-copy the .sea file to the hard disk. Double-click on the Disk First Aid 7.2.2.sea to unpack the application. Launch Disk First Aid, select the hard disk and click to verify. What does Disk First Aid report? Please post back.