I would call back my engineer and ask some questions.
How often does their company deal with this issue, and what are their experience levels.
Just because your an engineer does not mean you understand theses issues. They sometimes just look their information up in a book, do the calculations and collect the $$.
If you do not feel comfortable with theses folks, ask around for someone else, it sounds like you where not satisfied.
Why did they not document what they saw when they did the investigation? This is what should have happened, and a report written.
Other than that, I have to agree with Neal, maybe it's just still movin around and it needs to be monitored.
Sometimes those cracks have already been there, but you just notice them now since you are understanding "what" to look for.
I'm not tryin to be a pain in the arse, I just think they need to communicate, and educate you better as to what you are seeing.
Keep us posted.