Davis & Sanford Tripod Query
It is entirely possible that what your son purchased on eBay is a genuine David & Sanford tripod and head, but we cannot be absolutely sure from your description. All David &Sanford tripods sold by Tiffen are clearly marked, but those over 17 years old (before Tiffen acquired the brand) may not have labels. Apparently the tripod was reworked and possibly repainted by whoever owned it. The extra screw holes you describe are definitely not standard, and we can only conjecture as to why they were drilled, but this is commonly done to mount a non-standard accessory or to adapt the tripod for some specialized use. Incidentally, the CG-series tripod is still in production, but the BB head is not. If you feel that the seller's description was inadequate or misleading, we suggest you contact the seller and try to return it. In any case, we wish you the best of luck.