Hi Gaetano,
Yes, it looks that way, solve-field used "--verify" mode and confirmed the input WCS in those index files.
I see one thing in the log that you might want to fix:
Warning: encountered two index files with the same INDEXID = 1114 and HEALPIX = -1: "/home/s5lab/Research/RGB_catalog/Index/index_rgb_11-14.fits" and "/home/s5lab/Research/RGB_catalog/Index/index_rgb_11-14.fits". Keeping both.
which probably means you have listed the index files twice, or maybe listed the files and also set the "autoindex" flag?
eg, maybe your config file has
add_path /home/s5lab/Research/RGB_catalog/Index
...
index index_rgb_11-14.fits
...
index index_rgb_11-14.fits
or
add_path /home/s5lab/Research/RGB_catalog/Index
...
index index_rgb_11-14.fits
...
autoindex
You don't need both :) It shouldn't cause any harm, but will take twice as long to solve!
cheers,
dustin