Extracting single, same pixel value from three separate Sentinel 2 files

Hello All,

I am trying to extract the value of a single pixel in three Sentinel 2 files. Two of the files are spectral bands from the same tile in jpeg2000 format downloaded from Earth Explorer. The third file is an NDVI file created from the first two files. It would seem the easiest thing to do is to create images from all three files, tile them and then look at the pixel info panel. Unfortunately, the NDVI image will not open due to a 'null" value problem of some kind. Anyone have another suggestion on how to extract the values of the same pixel in all three files?

Thanks, Norm