As for the vouchers, I agree with highupinthesky.
From what I remember when claiming with an agency before, they told me that I was not bound by the amount of the voucher I was given by the airline (Lufthansa in my case). According to EU 261, you are eligible for care regardless of the reasons behind the delay (-- I am mentioning that because the right to care is completely separate from the criteria for compensation).
So, if you have your receipts you can ask for a refund for whatever your expenses were. The airline that should pay is the airline that is operating the delay/missed connection/cancellation.

I am throwing it out there because a) it sounds wild but you can get (hopefully not milk) considerably more than a voucher and b) I hope that when people visit this thread they would learn something new and very useful

SOURCE: https://skyrefund.com/en/blog/right-...inks-and-hotel