I am not sure I understand this issue. I know there was an issue with very long files names for Sentinel-2 data, which was a limitation in Windows as described here:
http://www.harrisgeospati...s-in-ENVI-53531.aspx I have not seen this behavior with a sample Pleiades Tristereo bundle data set but the file name/directory structure is not that long. For example:
C:\Testing\Test Data\Pleiadas\PRIMARY_TRISTEREO_BUNDLE\IMG_PHR1A_MS_006\DIM_PHR1A_MS_201202250025599_SEN_IPU_20120509_2001-012.XML
Can you show an example directory structure where this has been a problem that is different than what is discussed in the help article?