What are the health insurance requirements for Non-Immigrant OA Visa holders in Thailand?

I am a expat from the USA living in a condo I purchased in Cha Am in December 2018.

I received my first Non-Immigrant OA Multi-entry visa January 22, 2019 in Los Angeles with a expiration date of January 21, 2020. I checked in with Thai Immigration every 90 days as required

I traveled to Los Angeles on September 3, 2019 and returned to Bangkok on September 19, 2019 and my passport was stamped by Thai Immigration allowing me to stay until September 17, 2020

I was scheduled to fly to Singapore on October 5, 2019 and to return on October 11, 2019. A friend told me I would need a re-entry permit so prior to my trip to Singapore I went to the Thai Immigration office in Phetchaburi and was issued a Re-entry permit. While I was at Thai Immigration for the re-entry permit, I may have misunderstood but I thought the officer told me I would have to come in to extend my Non IMM OA visa in January 2020 prior to my original expiration date as stated on the Visa.

While preparing to for the one year extension I discovered the health insurance requirements for OA Visa holders that went into effect October 2019. It was my understanding the health insurance would be required when applying for a one year extension after October 2019.

I secured health insurance from Pacific Cross with the proper limits effective January 20 2020. There were so many exclusions on the policy that the insurance was basically worthless at a cost of 37,000 baht, but when I went to the Phetchaburi Immigration office prior to purchase of the insurance to inquire if there were alternatives such as depositing more cash in my Thai bank account I was told by immigration that such an alternative did not exist so I reluctantly purchased the health insurance policy from Pacific Cross Insurance.

When I went to the Phetchaburi Immigration office on January 20, 2020 to extend my Non IMM OA visa I was told this time thatI was not required to extend my visa until 45 days prior to September 17, 2020 and I was misinformed before about the extension date required in January 2020.

Since the insurance was basically worthless and I had more time to research other companies prior to September 2020, I canceled the insurance with the hope that I could find something better.

When I was at the Phetchaburi Immigration office January 20th I informed them I had tentative plans to visit family in California in April of this year and I was told since this trip was being scheduled after my original visa expiration date of January 21, 2020 I will be required to get a re-entry permit prior to leaving on this trip so I could re-enter Thailand when I return in April 2020.

I have the following questions:

When I return from Los Angeles in April 2020 will I be required to have health insurance in place even though I am not required to renew my Non IMM OA visa until September 17, 2020?

What is the best resource to access to fully understand the details of all Thai Visa requirements?

Is it possible to deposit more cash in my Thai bank account instead of buying worthless health insurance?

Can anyone refer me to a website or a Visa service where the Thai visa rules are defined in great detail?

I am sorry for the length and detail of this request.

I am a guest in Thailand and enjoy living here very much. I just want to make sure I understand all Visa requirements so I do not make a mistake.

Thanking you in advance for all of your advice.