While you can use the print macro to evaluate markup, and it will be parsed correctly, it's really not the recommended solution. That is, you're looking for program control, and should probably use one of the program control macros, but combine it with an either() to create the randomization that you want. That might look something like this:
<<set _sel to either(0, 1)>>\
<<switch _sel>>\
<<case 0>>\
<<button [[What does that mean?]]>>...<</button>>
<<case 1>>\
<<button [[You now have to decide what to do next.]]>>...<</button>>
<</switch>>
Note that you don't have to (and shouldn't) quote your double-square bracket markup when it's passed to a macro as an argument.