I'm kinda new to the game but I did a lot research and I did read that the D-bol that your describing is good gear, I would still do some more research if I were you.
There are no real ways to tell %100 if they are legit besides lab tests. But there are some tests that you can perform. Push down on the tab on a hard surface. If the tab breaks into a powder it's bunk. If it doesn't break or breaks into large clumps it's legit. Also dbol should have a slightly sweet taste at first and then a bitter taste similar to aspirin...
Exactly how hard did you press down on the tab? The dbol that I've seen the tab would probably go through my thumb before they broke apart. They're really hard to break using just your thumb. You may have some bad stuff. There's only one way to find out now. Start using them and you'll find out in a week or so if they're legit...