The European Space Agency community
I wonder how dual-use the technology is. A submarine-based nuclear strike capability could be useful to a country in Poland’s location, as could the hint of one, or the suggestion of being able to contribute to a joint European one.
I'd wager the line between "single-staged suborbital rocket" and ICBM is blurry af.
I would suggest that this project, that is part ran by the Military Institute of Armament Technology, is not particularly dual use - in that the research benefit of suborbital single stage rockets is vanishingly slim. It is however immediately apparent how much military utility such a launch system has…
Edit: actually on reflection its research capability has become clear to me - it will be extremely useful for researchers who are trying to advance the technology in the fields of ICBM guidance, control, navigation, targeting etc modules.