Good question if your flight is originating in AMS. Maybe if you show your DL card, they will let you in? Assuming you are DM/STE+ as your profile suggests of course.

OTP is usually an O&D for me so I use the lounge every time I fly out (at least once a year). They usually give me a voucher/pass when I check in at the desk.

There is no real difference between the Tarom Lounge and the Business lounge on the other side. I've used both and I felt like they were almost identical.