List of all Tube NaPTANs and their commonName in JSON and CSV format
you should try https://naptan.app.dft.gov.uk/DataRequest/Naptan.ashx?format=csv&LA=490 the LA= code is Grater London it will contain all the NaPTAN files for London.
That dataset complete forgets the tube exists and just does not provide an NaPTAN IDs for it. It’s the same with the data from the official government website. I sent them an email but have yet to receive a response.
With regards to the 490 codes these are used for Bus Stops and entrance points to stations in the London area. For LUL stations details you will need to use 940, Bank for example is 940GZZDLBNK and 910 where they have an interchange with National Rail (including TfL Rail and London Overground) West Ham for example is 910GWHAMHL
( cc @GerardButler for reference)