Builder wants to patch foundation cracks instead of following the engineer’s repair plan

I’m comparing two proposed ways to resolve cracking in a new-home foundation before drywall begins:

1. Accept the builder’s proposal to seal the visible cracks with epoxy and monitor them.
2. Require the builder to follow the structural engineer’s written recommendation, which calls for further evaluation, crack injection, and repair of the exterior waterproofing before finishes conceal the work.

The builder says the cracks are typical shrinkage and that the simpler repair is sufficient. However, the engineer’s report distinguishes the cracks from ordinary hairline shrinkage and recommends documenting moisture conditions and verifying the repair afterward.

I’m planning to send one written notice summarizing the cracks, dates observed, photos, the engineer’s report, and the requested corrective action. I also want to review the contract’s inspection, warranty, notice, and dispute-resolution provisions before agreeing to anything.

Would it be reasonable to request an independent structural engineer’s opinion before choosing between these options? If the builder refuses or proceeds with drywall, should I pursue mediation first, or seek legal advice immediately? I’m especially interested in how others preserved their rights without unnecessarily escalating the dispute.