The meaning of the mark in GC in not obvious. At the first glance we have a full bar hairpin 
, which was interpreted as such by the engraver or revisor of GE and notated above the RH part as diminuendo must have seemed more reeasonable. However, the GC notation implies clearly that the mark does not apply solely to LH but the A1-A octave in particular, which also allows it to be seen as a long accent. FE confirms such interpretetation, where the ocatve is marked with a typical long accent.
Compare the passage in the sources »
category imprint: Differences between sources
issues: Long accents, GE revisions
notation: Articulation, Accents, Hairpins