I don't know much about either program but am currently in an in-person SMP.
My question to you is do you think you would be able to balance a FT job, 20+ volunteer hours a week, and your SMP? Just because it's online, doesn't mean that there won't be any work to do with it.
The only difference between online and in-person is you take out the travel time. Other than that, you still need to find to dedicate the hours to the program.
With that, I would assume that doing well in a specific program would help you get into that program's medical school if it were to have one (I know Liberty has a DO, only one in Colorado I think is RVU-COM). I'm not sure how other schools will view an online SMP vs. an in-person one. I think you would have to ask individual schools.