Are you sure you put the right roster with the right ROM? There are two types of rosters for the hacked and non-hacked versions. One has the Texans and one doesn't.
So here's what I did:
1. I downloaded a fresh copy of NFL Blitz 2000 Rom
2. Patched Fresh Rom with XdeltaUI version of blitz 10 team xdelta file (the 11 team xdelta file gives error when trying to patch)
3. Selected Roster Importer to N64/Zoinkitty Blitz 10 Hack
4. Selected Load Roster File to Idabadas's updated roster
5. Patched Rom
6. Rosters are up to date but all players are beefed up and skin colors are different