Yes, the Isabella was made by Borgward. I had 2 in the late 60's/early 70's!
My dad bought an Isabella TS (touring sport?) 2-door sedan, which I 'inherited' my sophomore college year. It had been stranded in the garage with a broken left rear coil spring (IRS).
The support for the IRS rusted and allowed the spring to deflect outward. For about a month there was a strange scrape followed by a sproing sound each time my parents would pull into the drive way. Then one day, it was scrape, bonk and it sagged low on the rear where I was seated. They were only able to pull it in the garage - the wheel rim had finally wore through the spring!
I was given the car for college, if I could get it out of the garage. That's where the 2nd Isabella came in - a wagon owned by a buddy of my dad's. It was also parked in a garage, not running. It became the donor for the black TS.
I have a lot of stories about my (mis)adventures in the TS, like the 1st drive with all my friends down the main street of Syracuse, where the gas tank strap let go!
That car presented a lot of 'learning' opportunities, and was probably very influential in several job choices/opportunities.