there was no place for a Pz.Kpfw. II in neither the Stabsbatterie or the Geschütz-Batterien of a Pz.Art.Abt judged by the org. structures. These had either Pz.Beob.Wg. III or IV, and Sd.Kfz. 250, mainly /5 for these duties.
However, what the unit did under which the SP artillery was subordindated is a ccomplete different matter. It is possible that single or more Pz.Kpfw. II where commandeered to the SP artillery units, in order to simply help them doing their job.
In this case the workshop would have had to do a miracle in getting the extended radio equipment in this small tank.
so I am pretty sure that T.J. is right. There was never a Pz.Beob.Wg II, or a Bef.Pz. II command tank produced by the German industry. Customized solutions are thinkable, but were very badly documented. The few photos of modified Pz II known may tell much, but not the reason why they have been built. Did they help leading the Abteilung, the Batterie or the fire fight?