I don't believe "buying it to keep it off the market for our own good", I'm sure it was buying it to jumpstart a new product and the design turned out to be crap.
I dont believe that either. I mean, maybe it is part of the reason, but not the entire story.
I do believe it was basically that the Apollo´s design had something that Jens needed to learn/see how to implement in his own ACA accelerators, and also that by buying the design, he could prevent some kind of competition showing up.