Ok i think this is to risky or what you mean?
Ah sorry I thought there were a S-OFF available for One Mini..
Btw the command I said with "fastboot boot recovery.img" should work only on S-ON.
Maybe someothers can help but I think the only ways were the ones I explained:
"fastboot boot recovery.img" with S-ON
adb shell "dd=if....etc..." only for rooted devices S-ON/S-OFF
And if there were a S-OFF available for One Mini, the thread linked.
Sorry for not helping you.. Hope someone know another method..
xpirt