Hey!
A few things.. Did you add the known san pedro in one of those lanes, to compare? If so, and it appeared the same, that's a good sign. Were all the reactions the same in all cact?
Also, can you please describe (or video) the other reactions apart from Lieberman? Lieberman does turn black with mescaline. Its been a while since I tested mescaline, cant remember if on the plates the black from that reaction disappeared. Did you try Marquis too? Did it turn clearly orange/red?
Did you read the thread I linked earlier? In there, I put the
reaction database link, you can use for comparison.
Another idea when results are inconclusive, you can try doing a small drytek extraction on small amounts that cact just to see if it shows better on the plate. And/or you can play around with concentration of the sample too, try it more and also less concentrated, you may see better what's there.
Thanks for sharing the results!