I'm sure others will make you more paranoid with the sky is falling posts, but he did a good job. Dicor does not stick to dirt. If you use water or alcohol it doesn't matter as long as it is clean.
If the prior Dicor was sticking to the membrane, then just a lite application of new stuff to fill in the cracks is all that is needed. There is a reason the guy has 5 stars, and a lot of customers.
You see it's the cracks that cause the damage. Water gets into them and work it's way down to the membrane. That section of Dicor will then lift off the membrane allowing water intrusion.