The problem is that when using pure BTC with the “dividend” feature, all it’s doing is a standard “sendmany” bitcoin command, and it is restricted by the dust limit (5500 satoshis IIRC). When using a counterparty token for payment instead of BTC, it’s recorded as an actual “dividend” type transaction and has no value restriction. Basically that means that if any of your token holders would receive a payment below the BTC dust limit, they simply get ignored, which is why some holders were not included in your tx that you linked to.
I ran into this exact problem a long time ago with my own dividend paying tokens - EARNFREEBTC and SPECULATE. To get around it, I created a “proxy token” called BITCOINEX, which is trade-able 1:1 with regular BTC. It allows token holders to receive dividend payments all the way down to 1 satoshi, and then they can let it build up until they have enough to trade in for real bitcoin. See here for more details: https://letstalkbitcoin.com/forum/post/bitcoinexxcp-and-the-counterparty-gateway