Late Roman Army during the 5th century

[Robert Vermaat]

I would argue that the Notitia Dignitatum was an Ideal organization of the Army listing paper strength units; the army itself probably only numbered around 90,000 in the West, and about 12000 in the East (Paper Strength).

You are mistaken.
The Notitia Dignitatum never mentions numbers. Only is we try to add numbers to the units mentioned in the Notitia we can arrive at a total. As I argues earlier, that might be a number of 450.000.

The west fell because of money - the west never had the money to sustain an adequate defense force without help from the Eastern Empire's rich provinces of Egypt and Anatolia.

I think I can agree there, as least that it was one of the main reasons. On the other hand, much money was spent paying short-term federates (as well know, temps cost more) while the ensuing civil wars probably made it impossible to train enough soldiers for the regular army.