They don't know what they are talking about. There is no AMD or Intel "compatible" RAM. RAM is RAM. It's either compatible with the standard of your motherboard and CPU, or it's not. If your board and cpu use DDR2, that's what you get. If you need DDR3, and it's a very old DDR3 system, you may need low density chips, but most hardware from the last few generations all use high density DDR3 modules so for the sake of argument, we'll say the same here, DDR3 for DDR3. DDR4 for boards and CPUs that call for that. There is no DDR AMD or DDR Intel memory. It's likely they are not technically inclined and since the system it was removed from was an AMD system, that's what they're calling it.
Always, ALWAYS, go by what your motherboard indicates is the correct memory. Pretty much all motherboards have a product page somewhere that lists the specifications and what memory is supported. Very old motherboards or some OEM motherboards may be hard to find that data for, but it's somewhere.