Dinosaur DNA has, I gather, always been too fragmentary to give any clues as to which jigsaw piece they may be. It takes three "letters" to code for one amino acid so you need several triplets to stand a change of working out what kind of protein it is coding for (some, like collagen, have a predictable repeating pattern).
Your best bet for retrieving a sample big enough to do PCR and sequencing is by drilling into the teeth. Bacteria should have had a hard time penetrating to there although, for mineralisation, every inch has been percolated for millenia by mineral solutions, so it is a wonder any DNA is recoverable at all. I would rather believe what jim said, that these are traces of microbial DNA, washed into rock crevices in recent centuries. One even needs to rationalise why no living thing has passed by and scavenged this morsel of vital nutrients.