I had the same problem with an aspen bedding which was very fine cut. Like confetti. That stuff just filled the mouth of one of my young BPs. I took her in the bathroom and used my finger and a Q-tip to get it out. I used the rest of that bedding for the rats and put the snake back on regular aspen chips. I have only ever had a problem with the stuff that is so small that it clumps in the mouth. I now use paper for some of the snakes and regular large aspen chip for some others.
That is a freaky experience. Im glad you fixed her up.