Not true, the video is right here and uploaded by a pro-Sisi media , with a title claiming they were agents trying to sabotage Egypt's position vis-a-vis the Dam. There is also a number of videos of pro-Sisi Egyptian TV personalities talking about the video, saying its proof they were working against Egypt's interests and didnt know how to confront the Ethiopia issue.
While I don't think the ethnic self-determination hopes, are sustainable in such a diverse country, I dont see how a unitary vision can be imposed militarily. Ethiopia needs to find a political settlement that finds a middle ground between the opposing views. I don't see a happy end-state where all the powerful currents now unleashed, will agree to go away quietly, because of a military victory.
To also be fair, should have to acknowledge that Abiy benefitted from the exact same ethnic nationalist currents, that he is now opposed. Just look how much the rhetoric has shifted across the landscape over the past few years. I remember many of Abiy's staunchest current supporters, calling him an Oromo trojan horse/stooge. While his former Oromo nationalist supporters, now call him a sell-out, and are making common cause with their previous enemy TPLF. Battle for power means everyone is moving around this musical chair of political expedience.