In summary, the case humidity with 2 dampit style humidifiers is holding steady with the soundhole reading 49% RH. The overall variation from highest (soundhole) to lowest (headstock at 30% RH) reading continues to be 19% RH. FYI, I have not opened the case since inserting the second humidifier.
The plan is to leave both humidifiers in place to monitor their behavior during the upcoming cold front - and to see how long they last before drying out in coming weeks.
The Musik Tent is currently holding at 46% RH at the soundhole and varying by 3% RH from highest 49% RH reading at strap button to 46% RH at both the neck/body and soundhole, since adjusting the filament yesterday to increase the humidity slightly. The first photo shows probe readings of headstock (top at 47% RH) and neck/body connection (bottom at 46% RH). See updated summary table below. More to come.