Her argument is that “Parliamentary assistants do not work for the Parliament. They are political assistants to elected officials, political by definition”, so basically she says they can do whatever they want with the EU Parliament money if it is the decision of an elected person, which is clearly not the rules for this fund and she knows it.
To make it juicer, they found records of her party members explicitly estimating that they should not do that because it is embezzlement.
For context, this comes from a time when her party wanted Frexit similarly to the Brexit party in the UK, which the same irrational arguments. So misusing EU money was completely aligned with their idea to damage the relation. Turns out, Frexit was very unpopular even within right wing French people, so they pivoted to some kind of small EU now.
Killing flies