Re: Dealing with dried out wood - how best to repair, fill and match?
Just sand, sand, sand, and then shellac, shellac, shellac.
Odds are that shellac was the original finish; to test, see if alcohol dissolves the finish; yes = shellac.
I buy clear shellac already mixed (Zinsser "sealcoat") but for dark shellac I mix my own in alcohol from flakes. Garnet shellac is a rich reddish antique tone, and it is dewaxed, so it stores well and does not have any drying issues; all dewaxed varieties, which includes sealcoat, have a better water-resistance; the don't seem to get white rings from glasses set on them.
Your color seems yellower, so perhaps "lemon shellac" flakes would render the closest color match.
Remove not the ancient landmark, which your fathers have set.