First video explains more about their build and rotation. Both are parsed on Iron Atro to get some raid buffs since that is expected in an organized raid. Both are doing way more than 50k.
I’m sure it’s possible. I don’t Stamplar much, but I think you would use Relequen + Deadly + Maarselok for the 6mil dummy (Lokke is usually better but requires synergies).
August Palatine Davadin Bloodstrake - Nord Dragon Knight - PC NA - Gray Host
Greymoor 6.0.7 PvP : Medium 2H/SnB The Destroyer
Dragonhold 5.2.11 PvE : Medium DW/2H The Blood Furnace
March 2021 (too lazy to add CP) PvP: Medium DW/Bow The Stabber