If the track/wheels are clean, maybe you need more power. If you had a way to temporarily try a variable power source it might show whether this is the case. I have switches on my non DCC layout that will balk with one power pack. But another pack that I have is more powerful and throws all of the switches all the time 100% without fail.
We use the Hare and Tortise combination to control two HO Shinohara Dual gage turnouts on a double loop track configuration. This configuration uses trigger tracks which work most of the the time, but around 20% of the time an engine will not trigger the turnout and throw the points. Has anyone else had this intermittent problem and what is the solution? Thanks!