The 90 day, a non-o visa - this is the one you can extend due to you having thai children - however I would look into doing other visas marriage visa perhaps student visa or a dtv if you meet the income requirements - you were rejected a tourist visa for the sole fact you were already in thailand over the alotted amount for a tourist. However after January 2026 the visa exempt limit will reset
yes a DTV is not a non-o visa however it is used for study and remote working still - the dependant visa is for your immediate family to follow you to thailand with proof of birth cert and marriage certificates as the non-o dependant visa reads i honestly didnt think it could be used for DTV but I found out different when I asked - it seems im the only one in this group that actually consults a thai immigration lawyer