IMO, 680.44 requires GFI protection for the your proposed installation.
The copy of the NEC that I have handy states that spa installations shall comply with parts I and IV, of which 680.44 is included.
The protection is required at the outlet (see definitions) & this doesn't matter if a receptacle is involved or not.
You might want to check into a Spa disconnect. These include a 50 amp GFI breaker in a NEMA 3R enclosure with separate neutral & equipment ground bus bars. Makes a neat job.
Tom