The Base64 colours selected for Advanced Labelling of a raster symbolised by stretch symbology are not honoured in the Contents pane legend if the steps are not equal.

Solución alternativa

1. Create the tile package as a TPK (not TPKX).
2. Open archive using 7-Zip.
3. Copy out mapserver.json.
4. Manually construct accurate Base64 image values.
5. Copy edited mapserver.json file back into the TPK.
6. Upload to ArcGIS Online.

Pasos para reproducir