Yes he had a quiet life with his wife. He was a sort of inspector of Russian schools and cadet schools in France ( as his father was in Russia, but of course on a rather much more "grand" level than his ).
He attended gatherings and meetings of Russian émigrés veterans.
He was very close to GD Boris and GD André and their wives. They visited frequently their respective houses and of course played poker and bridge together ( Mala=Mathilde was a fanatic player...).
He also adviced his young cousin GD Wladimir Kirilovich, after his father's death. He organized sort of Russian patriotic programs during the war for young people in the Russian lycées, but happily GD Wladimir and GD Gavriil weren't seduced by the Germans, and were not involved in Kazem-Beck's Young Russians movement. On the contrary of GD Dimitri Pavlovich and Vova ( GD André's son) who were much more close to this organization before the war.
After Nina's death in 1950, he married Princess Irène Kourakine, and died peacefully in 1955 in Paris.
On this photography he plays golf at Mont Dore Golf Club, France July 1939.

Prince ( later Grand Duke) Gavriil was very tall and slim.