The case bracket expression [\ space\'\"] listed the letters s,p,a,c,e
as a character set instead of matching whitespace, rejecting every normal
path. Use the POSIX [[:space:]] class.
The inline find -exec broke through the double shell hop (the remote
shell consumed the ; separator). The script pipes its payload to remote
bash via stdin, tolerates zero matches, and fails loudly on missing
directories or failed moves.