Ditto on Chips comments. I've used Procion dyes successfully on some test panels. These dyes will not dissolve in epoxy but can be applied with water (they are powders). Bleeding is your biggest problem if you are trying to create a design. On the test panels I was able to keep the colors separate by 1) changing the wood orientation at the design edge, 2) scoring the design edge with a sharp utility knife, and 3) applying the dye as dry as possible with a sponge. Changing the orientation means creating accent strips on the design edge. This was obviously a simple test and more detailed designs would not easily work this way. Some of the results can be found at the link below.

Fading is your other concern, especially with red/orange tones. The sample I made was black (the orange color is natural WRC) and has not faded, but it has not been in the sun either. Best for you to try out a few test panels yourself before committing it to your work.

Bill