Personally I highly doubt Motorola and Verizon have some secretive plan to close down Android. At the moment Android is the biggest thing that Verizon's got in the Smartphone segment. Windows Mobile is in a tail slide and Blackberry is still considered something of a niche product. So unless Verizon is planning to jump ship to HP and WebOS I think it wouldn't do well for them to take on Google's flagship mobile product.
As for Motorola they've got enough problems of their own that an "end around" could cost them more than they're willing to absorb. Remember that prior to the Droid the last really successful Motorola cell phone was the RAZR (which, I believe, hit the market in late 2004). Their cellular division has not been doing well the last few years. And Motorola just spun off the division in an attempt to try to rebuild around their new partnership with Google. Again... a really good reason not to mess with Android.
Motorola Unit to Be Spun Off With $3.5 Billion - BusinessWeek