All
I don't think the French called them anything but Ju 188, and with just four of them being delivered, I don't even think they bothered which sub-type it was. J-P Dubois does not quote any French document where the actual sub-type is stated. Neither did A.A.B. give any formal type designation to either the Ju 88 nor Ju 188. They were known/referred to in official documents as either Ju 88 and Ju 188.
Just one comment to Franck's list of No 3. J-P Dubois is not 100% clear when No 3 actually arrived. Reason is that he refers to the quarter of the year (trimestre).
The code 10.S-12 was initially applied to No 2 (arrived 30.8.1946) and it carried that code in/beginning of the fourth quarter of 1946.
The code 10.S-12 is known to have been applied to No 3 in the second quarter of 1947. J-P Dubois is not entirely clear but it may be possible that upon arrival to 10S No 3 actually carried the code 10.S-13.
I will have to ask him if he can expand on this subject
One final point, the 'code' F-YCJG in 1947 was a radio call sign only and the aircraft carried its 10.S-12 on the fuselage all the time.
Cheers
Stig