DPN evolved directly from AFM so it is not a surprise that people often assume that any commercial AFM can perform DPN experiments.  In fact, DPN does not require an AFM, and an AFM does not necessarily have real DPN capabilities.  There is an excellent analogy with scanning electron microscopy (SEM) and electron beam (E-beam) lithography.  E-beam evolved directly from SEM technology and both use a focused electron beam, but it is not possible to perform modern E-beam lithography experiments on a SEM that lacks the proper lithography hardware and software components.
It is also important to consider one of the unique characteristics of DPN, namely its force independence. With virtually all ink/substrate combinations, the same feature size will be patterned no matter how hard the tip is pressing down against the surface. As long as robust SiN tips are used, there is no need for complicated feedback electronics, no need for lasers, no need for quad photo-diodes, and no need for an AFM.