I find it odd that the export brace doubler is absent or removed. If it was removed, who ever removed was very careful to not score the cowl area from cutting the welds. I find this questionable. Also, why would this piece be removed, unless it was not there to begin with. I see this as a red flag.
Not sure what your referring to. The cowl top shown in the pictures is from another car so removing it would not have left any damage from the process and the replacement (or the poor effort of that process - shown in the picture file provided earlier in the thread not the ad) would be the reason for removing it originally from the body IMHO So if the pictures are all from the current car it seems to me logical and fit what we're seeing at least on that detail.
As mentioned in a duplicate thread the signs visible in the pictures suggest where the top of the cowl (the donor car) came from as Brian mentions above.