The IC Amsterdam - Berlin doubles as a regular intercity in the Netherlands so you should have no problems with that.
There's a dedicated pool of Class 1700 locomotives which work the IC Berlin between Amsterdam and Bad Bentheim. The remainder of the 1700 fleet hauls/pushes double deck coaches (DD-AR, DDM1) or is in long term storage. 1772, 1775 and 1781 have been sold.
The following locos work IC Berlin services: 1739, 1744, 1745, 1746, 1750, 1752, 1761, 1765.
You can find an entire list on
Somda.nl, which is up to date until May 31st 2018. There haven't been much changes to that list lately, as NS are awaiting the introduction of the new Sprinter fleet (CAF Civity).
Key:
terzijde = in storage
in dienst = in use
gesloopt = cut up
solitair / NSI = works IC Berlin services
DDM1 / DDAR = works with double deck coaches