Sorry - wasn't paying proper attention!
Imagine French could be more of a problem than Latin as it is compulsory to GCSE whereas Latin would only be for a year.
Also - think that the entrance exam may include French?
I would advise that they phone the school and ask to speak to the correct member of staff so they get the info. direct and can check on the lack of Latin & French. There is some info in the prospectus I think. I imagine a major issue with transferring from a comprehensive is whether they have kept pace - especially in Science, with the way it is now taught at CRGS. Could need to consider more coaching.....
Imagine with the sets they will make an 'educated guess' based on the entrance exam & report from the previous school. The year 9 sets are not totally fixed (a few boys moved Maths set last term)and they change again for year 10 anyway. Because it is so highly selective the setting isn't such a big deal. I heard of someone who was set 3 (of 4) for French & got A* at GCSE for example
Since the 13+ entry is a regular thing I am sure they have the setting issue sorted.
Sorry again for mis-reading your original post/not paying attention to who was posting!