Owning your own home

Ouch - is the teak itself glued down ? definitely looks like they used the wrong product. My only frame of ref is having had 5 finger parquet (tropical hardwood but don't know what) done - they sanded it smooth, collected the dust and mixed that with a resin/filler product and scraped that all over, let it set, re sanded and then finished with bona or junkers lacquer. Then my kids dragged chairs and toys across it and fucked it. *sigh

Last resort is to make a claim under S49 of Consumer Rights Act 2015, with using MCOL or in your local Country Court on the small claim track.

49 Service to be performed with reasonable care and skill
(1)Every contract to supply a service is to be treated as including a term that the trader must perform the service with reasonable care and skill.

You would need to familiarise yourself with the process & protocols*, but even then it's a bit of a toss of the coin.

* One of which is that you must attempt to resolve this out of the courts in the first instance. This may be to give them a chance to remedy the situation, or to refund part / all of the cost.

You might get quotes from elsewhere for remedying it, and ask for that back.