Judy, if I recall correctly, this is where the contractor installed a drain tile & then backfilled with rock; is this right?
If that's correct, we never did learn of how much rock was used & this was a concern. The only rock should have been coarse sand or at most 1" to 2" rounded rock placed around & a little above the drain tile. The rock need only surround the drain tile by a couple feet at most.
The other concern was if heavy equipment was used near the home to compact backfill, which should have been dirt, not rock. If they were driving heavy equipment over top of the backfill right next to the house to compact it, this could cause the basement walls to crack and, in my opinion, would have been a mistake by the contractor.
I would be contacting both a foundation expert & a structural engineer, in that order, or if possible have them meet with you at the same time. There will be areas of expertise needed from both on this, and together they could likely tell you more assuredly if the contractor did his work correctly or if he's giving you a load of fertilizer to cover his mistakes.