@Gavilan, The answer is YES!
Proof from my bench: The A3000 has 15Khz and 31Khz video.The NEC3D MultiSync has a standard 15 pin connector. The NEC3D connects to the 31Khz port and presto -- works.
With the 15 to 23 pin adapter (CBM 390682-01 which has an logic board 715A444-1 with chip MC74HCT08AN FFR9240) the NEC3D can be pulled into the 15Khz port and presto -- works.
What I truly detest is NEC-Mitsubushi protraying their legacy monitor page with only 30Khz minimum frequencies. I do not belittle you for questioning me. I enjoy being challenged.