Again, the team can't be focused solely on what position they're drafting, but rather the player they're drafting. If they're on the clock, and the top player on their board is a DL, and they can't/don't trade out of it, they take the DL.
You just never know what's going to happen once they start playing. What if Rat gets hurt again? Or Ware? You want the best player you could get to be able to replace them. I understand we're on very thin ice with safety, so they need to address it. But there's no law that says they need to do in the first round, just for the sake of drafting one.