Old fire damage (repaired) found during inspection

[Kent Verge]

We are in the inspection phase of a purchase (offer pending inspection) and found evidence of an undisclosed old fire in the attic that had been repaired. When I asked the seller about it, she said, "Oh yeah. I just saw that on the disclosure from when we bought the house and forgot to disclose it."

There's obvious repair, but my inspector said that he couldn't assess whether or not it was repaired properly; he said that I would need someone who specializes in fire repair. This evening a general contractor came by to price out the remodel, and when he saw the damage/repair, he expressed similar concerns (I should have a professional look at it).

Question: because it's very old, there is no odor in the attic (even sniffing the soot or very slight char on a few old rafters. I plan to enlist a specialist, but should I find a remediation person (think Servpro) or a structural engineer? My fear is that the former will recommend a bunch of smoke remediation (sealing, etc.) that is no longer an issue. I'm most concerned that it has proper structural repair.

Kent