I didn't make it out that he was a liar, i believe that he might not have known for sure if the horse was fragile before the race or not. Also, i don't want to use the word 'liar' because in this game and in life in general, there are 'little white lies' to protect people that don't want to get thrown to the wolves.

If the Doctor was a really nice guy, which i'm sure he is and he really likes Michael Matz, why would he say "yeah, the horse was flawed and thats why he broke down' Thats like saying "michael matz is to blame for running a horse he should have known was damaged"

You have to take this stuff into context. At this point, all that matters is barbaro's health. Whether he was flawed before the race or not absolutely doesn't matter one iota to anyone except maybe the insurance companies and the morbidly curious.

I don't believe its fair to say that "im calling the doctor a liar" because that is sort of indicating that i believe he is running a dishonest practice. I'm just saying that in order to protect trainer matz career, he said, "it was a fluke"

this doctor could ruin michael matz career if he said the guy ran a horse who was badly flawed.

No reason to throw matz under the bus and ruin his training career...just like the doctor wouldnt want anyone to ruin his livlehood.