Medicine year 1/2/3 tutor/lecturer and admissions tutor here.
As others have pointed out, your son needs to research the various delivery styles of different medical schools to see whether some of these suit him more than others.
At one extreme are "traditional" courses (quite rare nowadays), where you spend 2-3 years learning medical science then 3 years applying this in clinical settings. These are more likely to have a lot of memorizing in the first few years, but they are definitely not exclusively rote-learning.
At the other extreme are problem-based learning (PBL) courses, where you learn everything from clinical cases: groups of students have to identify essential learning points from cases, study them independently and then report them back to the group. To be honest, there aren't any pure PBL medical courses, however they might badge themselves: all have specific learning activities supporting the key areas students should have identifed as their learning points. While some PBL courses claim not to include lectures, they do all include lectures: they just call them something different (e.g. "plenaries").
You can summarize the difference between these as follows: in a traditional course you are told more or less exactly what you need to learn but only find out a few years later why you needed to learn it; in PBL you know exactly why you're learning stuff but you're not told explicitly which specific things you need to learn or in how much depth to learn them. Obviously, there are up- and down-sides to both of these, and students need to work out which will work best for them.
In between the extremes are "integrated" courses, which actually vary quite a lot in how far towards either extreme they lie. These will all include a range of different learning activities undertaken in groups of varying sizes.
Overall, any medical course will be predominantly classroom/lab-based in the early years (although some have very little lab-based learning) and predominantly ward/clinic/practice-based in the later years. All have some element of early patient contact but the extent and intensity of this varies enormously. At some medical schools you'll learn all of your communication skills and a lot of your basic clinical skills in GP surgeries with real patients; at others you'll learn these almost entirely in classrooms & skills labs with other students and simulated patients.
There are some areas of medicine that inevitably require a lot of memorizing. The main one is anatomy, where you have to learn the names of all the structures and what their blood supply, innervation and lymphatic drainage is. For muscles you have to know what they attach to at either end to understand what function will be lost if a muscle doesn't work properly. For blood vessels & nerves you have to know what structures they pass through or alongside to know what function will be lost if one of those structures is damaged or swollen. It's not quite your-hip-bone's-connected-to-your-thigh-bone but it's not a million miles away from that. You also have to learn stuff like which microorganisms are the most common causes of particular diseases, what the most common pathological causes of a particular symptom are, etc. Most of this kind of learning is much, much easier if you understand the underlying principles; unfortunately, a lot of students try just to memorize lists without understanding them, and they consequently have to work much harder.