Yes, it looks like a 1900 manufacture date is right.
FWIW, the serial number discrepancies are between the polishing room records (pre-assembly) and the shipping records (after assembly, often quite some time after assembly). Some experts like the polishing room records, mainly because polishing was one of the last steps in manufacturing before bluing and assembly, so it gives a pretty good idea of when a firearm was assembled. One problem with Winchester is that they would produce receivers in batches, then they drew from those batches (not always in order) during assembly. Also, custom firearms and special production firearms would be produced and stored for quite some time without wood because the wood would be special ordered by the customer. In either case, I think the numbers are probably close enough, it gives you an idea of when the firearm was produced.
Never try to educate someone who resists knowledge at all costs.
But what do I know?