We are travelling to Ko Pha-ngan and unsure on the Day 5 test requirement;
Our flights are UK to Denmark to Singapore to Bangkok (the Denmark to Bangkok is a single trip with short 1 hour stopover to change place in SIN)
When we arrive in BKK I know that currently we will need a SHA+ hotel and day 1 test - no problems here.
We plan to stay in Bangkok for 3 days and on the 4th day we will fly from BKK to USM (Koh Samui) and then boat to Ko Pha-ngan.

My question is in regards to the Day 5 test - will I need a SHA+ hotel in Ko-Pha-ngan and test to comply with current rules - we currently have a villa rented but they are not SHA+ compliant.
If I do need a SHA+ hotel, could I book any hotel so that I have the Thai Pass validated but then what happens if I don't actually use the Day5 booking?

Thank you in advance for any help and advice