Can someone help with an auto loan question?

So, I recently filed bankruptcy and it was recently discharged. I thought I try for a car since I've gotten more hours at work and my current car is falling apart. My friend suggested that I go through boss's car company and try to buy a car. She knew that my credit would be horrible and I knew what to expect for an APR rate. I told her to go through my credit union, a few minutes later, I get an email saying that I was denied. But, an hour later....I was told by my friend that I was approved for a 10k loan. To make the long story short, I didn't get the car but, my friend told me not to mention this loan when I go to other dealerships. Why would she say that and why would it matter?