RBMC error platform_read_file: fopen: Operation not permitted (version: 4.7)

Thanks @Indrajit for posting this information.

Given the project directories sshfs implementation, I wonder whether you ran into an issue similar to I/O error when accessing particle images in CryoSPARC v4.6.0 if SSD caching is turned off - #9 by meier.
What are the outputs of the following commands on the sgpu2 computer (as user spuser):

id
uname -a
ulimit -Hs
ulimit -Ss

?