Good to hear your success story! I’m having very good results also with the KS8.
I have a Galaxy S6 and the Smart Mic Bluetooth device and if Bluetooth is not on, the phone app communicates with the hearing aids using acoustic signals for remote functions. However, not all functions are active in acoustic mode. For example you can select the programs but there are also listening environments for program 1 like Cafe and Group Conversation, and those are grayed out in acoustic mode.
But, the Smart Mic is almost always on and that results in all the app options working.