Believe you're aupposed to Dig with a spade with items in your inventory.

I just tried digging around on the watchtower and the bridge, no effect...

I'm sure you've figured it out by now, but in case someone is wondering: for scavenger clues you generally need to USE one of the (generally three) items ON the SPECIFIED object, which will then grant you a new clue.

In case you did mean this by using the items, and the table does happen to be bugged for some reason, then sorry. Hope your issue is resolved

Yeah it was me was my first medium clue an we tried like everything maybe i didnt dig right tho it said just bring items to table i destroyed it mod terror gave me another medium right after i did an i finshed it an the rewards were strait shit being my first medium i was exspecting something good. Was interesting iam pretty sure the mod tried to fix it an said something about needing a new drive or somthing been awhile i forget