If the cracks and voids are truly cosmetic, you can use 5 minute epoxy mixed with teak sawdust to make the fill. When cured, the excess can be easily scraped, sanded, and finished. A quick way to make sawdust is to take a piece of scrap teak and 80 grit sandpaper. If you have a random orbit sander, blow out the dust collector and collect the teak dust.
I've used this process for years on a variety of woods including teak. It's a much more stable method than the classic technique of mixing sawdust with finish. The method was pioneered by Sam Maloof.
Sabre 38 "Victoria"