Not true. Ekectronic payments are not equal to electronic banking.
You are confused.
It's like a petrol card.... you give access to nothong more than the pre-advised funds nothing more nothing less. Needless to say these cards are not linked to the main accounts but hold only pre-advised funds
You can fly trough domestic from cnx to bkk. Then after your hotel visit in bkk city you can check in international in bkk.
If you check in international in cnx you have to stay within the transit zone in bkk. There is a hotel inside the transit zone however but its rather expensive.