The Royal Thai Embassy in Manila requires more documents than other countries. Here is some information replied by the consular when I aaked them via email.
Destination Thailand Visa (DTV)
(Workcation / Thai Soft Power Activities / Spouses and dependents of Primary DTV visa
1. Proof of purpose of visit
Workcation:
a.1 Employment Contract
a.2 Employment Certificate stating your scope of work while working remotely, and the nature/industry of your company/business
Professional portfolio showing your freelancer work
Thai Soft Power: Proof of confirmation to attend the activity or a letter of appointment from a hospital or medical center
Dependent of Primary DTV Holder: Proof of relationship, such as a Marriage Certificate, Birth Certificate, or Certificate of Adoption, and Photocopy of Passport and DTV of Primary Visa Holder
2. Bank Certification / Bank Statements from the last three months (Minimum of 500,000THB or the equivalent per applicant)
Local Bank accounts for those holding Philippine Resident Visas
If applicant will have a sponsor to shoulder all travel expenses: Guarantee Letter from sponsor (with a copy of sponsor's passport, and Bank Certificate or Bank Statements)
If applicant will be applying as Dependent of Primary DTV Holder: Bank Certification or Bank Statements should meet the minimum amount required per applicant (500,000THB minimum for 1 applicant)
