But yes, Poi Pet is hard, I would not bounce from there. 9k baht fast track service with Thai Visa Centre, or trying your luck in Chiang Mai airport or Langkawi by boat are all good options.
Julian is correct. It's still quite easy to border bounce. Did my third bounce of the year in Nong Khai about 3 weeks ago. I have 3 passport loaded with stamps. Before, it was 2 bounce per year by land, but some people were still able to do more if they enter from South Thailand, for example with a boat in Langkawi, or with help (tea money) at the border. Entering by air in Bangkok have been hard since 10 years ago! It's been a while. I've been here for much longer than Julian so i can confirm that he's correct.
Your situation is different. BKK airport have been strict for 7-8 years, even more so lately but they were already denied a lot of people. But you have a good chance of being allowed in by LAND. Bangkok airport is to be avoided. I haven't enter via Bangkok for 8 years.
It's the Thai - Laos Friendship Bridge. I've cross that bridge 20+ times, never heard of Saphan Mitaphap. You are the first ever case of denial entry in that border. You made a post August 31 in Bangkok about the IO questioning you. What is your history after that?