I also got asked for that document, actually is a sort of certification that proves that it's a 5star gym. Not all of the embassies require it but Taipei and KL have been requesting that for ages. I applied with wildcat in chiang mai and when the embassy asked me for the documents, the owner could provide them immediately. I highly recommend to apply with them
before I applied, I mailed them asking how to deal with a situation similar to yours. the embassy clearly asked me to put all the money in a single bank saving account. When I replied asking if that would be an issue for the seasoning part (I had well over 500k but none of my 3 accounts could reach that quota) they said that I could also prove multiple accounts. I did as required, I submitted 2 bank accounts with one having over 500k (just few days prior my application) and another one with 300k. After I applied, the embassy required me further documents showing the money going from the company I worked with into my account (even tho I applied for soft powers) . Keep that in mind and good luck
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