Think about what may need to happen when running an EA dish into the input of a 1000.2. The d1k2 has 3 outputs that can support 3 dual-tuner receivers by way of DishPro Plus selective stacking (one requested channel goes to the low range, the other from the same or a different satellite goes to the high range). The EA also has DPP outputs, so 2 channels can go on the line running into the d1k2. How can more than 2 tuners at a time of the potential 6 attached to the d1k2 have access to the EA? And no, AFAIK you can't get 2, only 1.
You can have 5 with a DPP44/DP21 cascade but won't be able to use the Separator with a dual-tuner receiver because the DP21 isn't a Plus switch. So, a DP21 and extra line for each tuner.
All of the cascade solutions for adding an additional satellite (just one) have the output of a 2- 3- or 4-satellite switch running into an SW21 (legacy) or DP21 (DishPro).