Was Nikolaos Zounaras, the thematic judge of Thrake and Makedonia, active in the Rus’ after the council of Liubech (1097)?

Nikolaos Zounaras / Zonaras served at the end of the eleventh century in the capacity of judge (κριτής) of the united themata of Thrake and Makedonia. There exist five of his seals found in the Byzantine territory to guarantee the exact transcription of the legend on his seal. He was, from 1088 onward, protovestarches and grand chartoularios and later became droungarios tes viglas in the first quarter of the twelfth century. It was an extraordinary surprise to find extant (up to this point) some 15 (sic!) seal fragments of this seal type in the Old Rus', especially in the knjažestvo of Chernigov / Chernihiv. The authors propose that Nikolaos was officially sent there by the Byzantine emperor to assist in a fair division of Chernigov between the two brothers, David and Oleg-Michael, as per the agreement of the Council of Liubech (1097). Zounaras's activity throws new light on the Byzantine Rus'ian relations during the reign of Alexios I Komnenos.