Sanders, try bleaching your tongs after use then scrubbing them off and see if this helps in general. Not sure exactly where the contamination is happening for your process, but the above suggestions are good ones.
If you decide to try an amidol developer, use cheap gloves and not tongs. I used an old set of tongs in the developer and have found that by repeated use, they can carry a bit of developer into the image from contact and pressure. Cheap gloves which you throw away are better in this case, as they get tossed before the problem surfaces (nitrile from Harbor Freight on sale at $7.99 a box). My amidol doesn't always dissolve 100% and can carry a small amount onto the surface which shows up as spots which can be rubbed off under water. I'm now using a coffee filter to get rid of the problem. tim