For a Non-O Immigrant (Retirement) visa, can I enter Thailand from any country?

tl;dr: For a Non-O Immigrant (Retirement) visa, do I have to enter Thailand from the country listed on the visa or from any country?

Details: I've applied for a Non-O visa on the Thai eVisa website ([members only]/). The process was straightforward once I knew how to do it and as far as I know the documents I submitted were good.

The Australian Thai consulate says the eVisa should take 10 business days except in high season (whatever that is) ([members only], scroll down to "Attention"). Since the visa application required an arrival date and flight number I booked a flight. My departure date is fast approaching and I'm worried I won't get the visa issued in time. I acknowledge this situation is "all on me" - for brevity I'm leaving out why I chose the date and flight that I did.

Possible options:

1) Cancel the current flight, wait for the visa to be issued, rebook the flight, travel to Thailand. Question: Does it matter if the arrival date and flight number is different from that on the visa application?

2) Book a second flight out of Thailand, say to Malaysia. I think (?) this will allow me to get on the flight using a tourist visa (visa on arrival), although 1) it's not a return flight to Australia - don't know if that's a problem, and 2) it's possible Malaysia would not let me enter without an outbound ticket. Enter Thailand, wait for the visa, fly to Malaysia, re-enter Thailand on my Non-O visa, minimal stay in Malaysia. Question(s): Same question as above. Also, for the Non-O visa do I have to enter Thailand from the country listed on the visa or can I enter from any overseas country i.e. Malaysia? Lastly, Thailand would know I was in Thailand when the visa was *issued*, although not when it was *used*. Is that a problem?

3) Same as #2 but have a return flight already booked out of Malaysia. This issue is when to book that flight - I don't know how long the Thai visa would take to get issued, regardless of what the Thai Consulate says.

I prefer option #2 but definitely want to stay on the right side of Thai immigration. In typing out these options #2 and #3 seem to be risky. Option #1 and eating the rebooking cost for the flight might be the safest approach. Your thoughts?

The eVisa website does list a number at the bottom of the home page: (+66) 2203-5000. I will call them Monday. This post is just to cover all bases in case calling that number goes nowhere.

Thanks...