I worked in medical research too, and there was one Chinese doctor that we all swore was a spy. Very little English, and he was a jerk. This was in the early 80’s. One time he just up and moved my experiment that was in process and took over the space. I wasn’t in that room for about 30 minutes so that I could prepare the next step of the procedure in another room. When I got back to check on my work, I found that he had moved my materials completely out of my work space, and set up his own experiment instead. I was furious! I completely lost it, and yelled, and went to my boss to tell him that now we would be behind schedule. I had to start everything over. I was 2/3 finished with my project! Luckily, I was able to reschedule rooms and equipment necessary again and got that portion of the experiment completed within a couple of days. I really gave that doctor a scolding, which was funny because I was just a tech and he was a visiting Ph.D. About a week later, he came back in my lab space with a silk scarf. I told him he didn’t need to do that, a simple apology was enough, but he insisted and my boss said I should keep it, so as not to offend, so I did take it home. I don’t think I ever used it. After a few years, I finally donated it. Anyway, yes, I agree with your granddaughter. It was hard to trust someone who wouldn’t speak English.
This....offend him...is a lot of crap. That’s how you lose your integrity. You had the upper hand....you should have kept it.