This is troubling. Given the value of this group is unincumbered advise independent from the self-serving agents that look to push people into that direction. The group rules included no mention of agents or agencies.
I did exactly that (using the banked funds method deposited on 17 Oct.) arriving in THA 30 Oct with a 30 day visa exempt stamp and a subsequent 30 day extension of stay. If you funded your account using a single bank to bank wire (vs. multiple Wise transfers), you will have an easier go. I would also advise using your first 30 days getting your permanent address nailed down and getting your TM30 buttoned up. Good luck.
My understanding is you can not hold 2 long stay visas simultaneously (non O/A, B, ED, etc.) in the same passport. I do know that if your using 1 passport, you would need to cancel one visa to have the other affixed. Elite will not allow affixure of the Elite visa if you do not cancel the non B first (which can be done in country). I don't know what you would do to cancel an Elite visa in country to get a non B affixed.