I recently found a 9 min YouTube clip from Sept 2019 of the Bonobos in Frankfurt and Margrit features in that.
Yes, she's the oldest to ever be in captivity, and likely the world. Seems to be a family thing - her daughter Daniela is one of the oldest females in captivity at present, and her son Mato is the oldest male ever in captivity (he's still alive today at the ripe old age of 57!)
The new year started with a birth at Planckendael. One year after the death of her last baby female NAYEMBI gave birth last night. Sire are HERI, NYOTA II or PANISCO in Frankfurt.
Birogu at Wuppertal euthanised on 15 December 2020 (translation suggests he was found to have serious internal injuries and the decision was taken not to revive him from anaesthetic).
Well, at least Rhenen has build a splendid enclosure designated for bonobo's. It should be nice the first ones will arrive!
I have found a link below. Sadly, my German is bad so I was unable to find the information I was looking for but still interesting none the less. https://www.koelnerzoo.de/images/pdf/Zeitschriften/Zoo_Masterplan_2030_Web.pdf