If it smells like mold, well it probably is mold.
I have seen it in 1 year old homes.
First get your inspector back to see if he missed something and give them a chance to make it right.
And talk to him about getting a real stucco inspector out there. One with a moisture meter and probe. The thermal cameras will only show if there is a temperature differential. You need to know if it is wet.
Also get ready for some exploratory lookin. You will probably have to cut into the suspected area to know for sure. This is typical of leaking stucco issues.
First find out what the issues are and documented. Then contact the pay up people.