Stumped

I'd like to enlist the power of readers to find out more about Baron Jan Otto Wilhelm Stahl Von Holstein, who was a director of Kids Company for ten years from 1998. Company records suggest he was born in June 1939. He's been a director of three other companies I can find, Cerebrum and Rampus International (both dissolved) and Franka Couture.

Franka Couture is the dress-making operation of Baroness Franka de Stael von Holstein (slightly different spelling, but presumably a relation). The Baroness made the wedding dress for Lady Rose Windsor; a gown for Ava Gardner; and some of her creations are in the V&A. She's said to have come to London in 1961, and worked initially for one of the Queen's favourite dress-makers, Norman Hartnell.