Would like to see pix. Streaking in clear glass is fairly common.
However, that doesn't appear to be what you're describing. If the "thump print" is between the glass and the lamination, not on top of the glass, then the limb has delaminated in that area, probably due to a starved glue joint during the build or a nick or mar in the finish on the side of the limb that allowed moisture to enter.
Depending on the location and extent, it may not be safe to shoot and it may or may not be repairable.