These are the Bands statistics, tbh I was expecting (hoping) to see the “-1051” value in a No-Data column, then it would be clear which values to filter out 
In this case it’s a source data issue,
For now, I’d suggest to clean the data before sending, e.g. using Raster-> Raster Calculator:
P.S. The higher is the resolution of the satellite (texture) image, the longer it will take, in this case the size is over 1000x1000 cells, so more than a million little mesh faces.