I think the point RJ was trying to make is that most colleges/universities are accredited as a real, legitimate college (not the degree-mill, fake, all about profit "colleges"). Giving out degrees that any employer will take. Then some other body may decide to give a preference by bestowing their "accredidation" for a specific program; but this does not legitimize the college as a whole, it just recognizes the relevance of that one program. So you can get a perfectly recognized degree from an affordable state college or university (at minimal cost compared to private colleges) that will probably be perfectly adequate to get 99% of planning jobs out there. The fact that some special interest group has "accredited" a college probably means they've been paid to promote that college. In any event, "accredidation" from special interest groups is NOT the same as "accredidation" from a recognized body that accredits colleges. I guess it's just a special stamp of approval and really shouldn't be called accredidation.
I think what everyone is trying to say is just adding degrees at some expensive school isn't necessarily going to help you financially in the long run. You'd probably be sufficiently served by an affordable state planning school that has a strong design component.
In my experience urban designers in the "planning" sense means designing at a much more conceptual scale ("bubble plans" or conceptual land use plans). Architects deal with buildings, with limited site planning (usually for smaller sites dominated by the building(s)). Landscape architects don't do grading, etc., but rather plan out the spaces left over by either the architect, or design spaces set aside by planners (e.g., parks). And of course, engineers are the true site designers (especially for larger sites where grading and other engineering elements - e.g., sewer - have a larger impact on the design) - though engineers often base their designs on conceptual plans made by planners.
I have not met in my career an urban planning architectural landscape architect engineer (much as some would like to think they're all four). I would recommend choosing a scale you'd like to work at, and then pursue a degree in that field. For example, if your goal is to design buildings and their immediate surroundings (i.e., in more than just a conceptual sense), planning may not be the right path for you.