I usually find an open defrost heater on these.
I always check resistance on these whenever I have the cover off as a practice.
You can replace the heater, but you have to order the whole evap assy. Samsung's official position on these is that you must replace the evap, which is, of course, a sealed system repair. If it falls within the sealed system warranty period for this model (5 years), then parts and labor would be fully covered by Samsung. You could just charge the customer for your diagnosis and refer them to Samsung to have an ASC/MSC complete the repair (assuming you not authorized).
Outside of the 5 years, you could order the complete evap assy and just remove the heater and attach it to the existing evap without opening the sealed system. It's a bit of a pain the first time you do it, but overall there are worse jobs you could do. Just give yourself some extra time. I have done quite a few and still make sure I have a solid hour to complete the job.
FYI the freezer evap p/n is: DA96-00612G