Having read the article, there are three issues I have:
1. The writer does not show what he thinks has perpetuated the 'glorification' and 'mythbuilding' in the historiography, not what its current status is. He merely keeps repeating Colenbrander's work as the basis for the fact that the Dutch 'all seem to think that all 15,000 Dutch troops that went into Russia perished'. This despite the fact that over recent years, many historians have undertaken work in this direction, as Napoleonic memoirs have started to crop up and interest in Dutch national history has grown. The 'myth' has to be supported by more than just Colenbrander's work.
2. Numbers. The writer uses the 1810 strengths of the formal Kingdom of Holland military units to ascertain total strengths of French military units in 1812, includes the 131st regiment which in a footnote is shown not to be solely composed of Dutch soldiers, but excludes Armed Citizenry, Colonial troops, Naval gunners posted in shore batteries etc.This makes for a dodgy total.
3. Time period. The writer originally focuses on 'the Russian campaign', meaning the campaign in Russia proper in 1812. But later he includes the entire 1813 campaign, when 'Dutch' French battalions still hang on in Baltic and German fortresses etc. But if we were to include the 1813 campaign in his story, we would then also have to include the military units that were created in 1813 from National Guardsmen from the Dutch Departments (136th-140-odd Regiments of Line Infantry) as well as the Dutch-recruited Guards of Honour units attached to the Imperial Guard.

All in all the writer makes some interesting points. But he does not clarify sufficiently what ultimate point he is trying to make. Were the three battalions of the Orange Legion that were recruited in Prussia the core of the new Dutch army? Hardly. Were there more Dutch survivors of the Russian campaign than previously thought? Possibly, but taking into account the fact that 4th and 5th battalions of the 123rd-126th regiments were all left in fortresses that was never going to be surprising. And if we then add the Dutch survivors of the 136th-140th Regiments of the 1813 campaign, it becomes even less exceptional.