How To Treat Eucalyptus Garden Furniture

Edit: I called Wayfair and talked them about your professional opinions. They said if I followed the instructions with the new table and if it had the same problems they would refund the money and their design team would find comparable tables. Yay! So given what you all are saying maybe I shouldn't risk the warranty with another marine varnish that isn't permitted technically. So next table I will make sure it is white oak or teak. Pretty happy with Wayfair because I have had the 1st table for 1 week shy of a year.

They said that the manufacturer had gotten back to them about what to use on it besides the liquid wax that was in the warranty info. They said I should use Starbright Premium Golden Teak Oil. Which is the exact kind that I have and wouldn't absorb. Maybe the Sikken kept it from absorbing in the 1st table?

Edit: Thank you for your help so won't use the shellac for the new table. I found this info and would like to know if you agree. I added some pictures of the old table that's less than a year old. I found more info on the type of Eucalyptus, it's Eucalyptus Grandis (also called Red Grandis, Rose Gum, Flooded Gum, Scrub Gum) and prone to insect problems unlike other types of Eucalyptus.

The commenter said they professionally sealed yacht exterior teak and to make sure it adheres to the oily wood by thinning it and using the marine varnish for Seal Coat (1st & 2nd coats). 1st coat of Epiphanes thinned by 50% & 2nd coat thinned by 20-25%. Build up coats thinned by 10%.

This is for teak not eucalyptus but does seem like simpler is better and I see much more about Epiphanes on the site then the other product in the article mentioned in the post.
Questions
1) Should I sand new table before applying 1st coat and between coats? Grit?
2) should I thin with Mineral Spirit or Denatured Alcohol?
3) is my top coat undiluted? It sounded like that's what he was saying bc he mentioned having a separate pint for top coat bc of curing as soon as the can is opened?

Original Post

It's warping, cracking and pulling apart after less then a year. I have treated it with Sikken Cetrol on two different occasions and water still gets in no problem and tiny black mold colonies are growing all over. I complained and they sent me new table to replace other one but need to do something different. I am not a wood worker so any specific product recommendations would be greatly appreciated. The Sikken took a long time to dry. Is this bc of oily wood? But did nothing to prevent the water from getting in. I don't see a consensus on how to treat Eucalyptus other then wipe up water very quickly and keep it out of the sun bc it doesn't like either. It gets partial sun and I frequently cover. I read a helpful article on this site suggesting to seal the oils in and not trying to draw them out with acetone with Wax Free Zinsser SealCoat and then Shellac to protect. Is this the best course of action, that article was about oily woods and not specific to Eucalyptus or being outdoors? Also, should I sand the new table before SealCoat? The manufacture says only to use liquid wax. It's a Lazy Boy table so I would really appreciate anyone's help. If it helps Wood from Forest FSC C102108 This is the table https://www.wayfair.com/outdoor/pdp/la-z-boy-cumberland-wooden-dining-table-lzbo1031.html