Only just caught up with this thread and a quick google search reveals that RIT dye is more suited to fabric and maybe that is where it has all started to go wrong for you.

As King Casey mentioned Stamp Pad ink is rubbish and presume the indian ink he used was for fountain pens? In my signature there is a Red J Bass that was done in a combination of fountain pen ink and watered down colortone cherry with more than 20 coats of Tru Oil all over.

If that finish is coming off now it will keep on going so maybe better to sand back and start again. For a glitter finish I would experiment with adding some into a small amount of the preferred top coat whether that be Tru Oil or another similar varnish or lacquer type product and shake it up so that the particles become suspended in the liquid about to be applied. No doubt it will feel gritty as it goes on but if used with an oil based finish that will help it stick and stay put. Once you have the glitter layer looking schmick time to revert to just a few thick clear top coats to help fill any dips and gaps in the surface and then gradually add a few more thinned top coats to bring up a smoother surface.

Just my 2c worth and yes a bit of a step backwards but worth it in the long run IMO.

Cheers, Waz