Jer,
Thank you for posting the photos and your added information. Having dedicated 15+ years of my fishkeeping experience to almost only peacock bass, I will be the first to admit that my cichlidgeekiness has suffered greatly in the areas of other species and genera. That said, I always had a very strong interest in pike cichlids from an early age, but chose to focus on peacock bass instead. Many of you know the success that I have had with Cichla, and many of you also know the failures I have endured as well.
Moving on......I was fortunate to see several dozen Xingu II imported fresh from Brazil several times over a period of maybe 3-5 years. That was so long ago, however, that the time period is just a blur now. All were fresh imports and only a handful were retained by a "then friend" for a breeding project. Of course, that never happened.
The mystery pike that you have now and the real Xingu II that you had a while back are not the same fish. I hesitate to say that with such a cocky certainty, and I hate to say that even more so based on a few photos. I apologize for that, as I am really not trying to be a jerk. Please know that I have never seen Xingu II with such heavy spotting in the face and nape region at such a late stage regardless of maturity and what not. There is another reason for my statement, but that will be through PM. I hope you understand.
Now, in reality I have to admit that it appears as though from early on in the ID game there would be a certain level of disappointment if these pike turned out to be something 'common.' That is a shame in and of itself. They are beautiful specimens and there is no doubt that you can grow some seriously nice show-quality fishes! Your lents, for example, are really the nicest lents that I have ever seen.
Ok, well that's all I have for now. I will reply to your PMs here shortly.
Cheers,
--Brian