The data you have posted is a perfect demonstration why relying on proc import is a bad idea. Instead of reading the first variable as char, the contents of the variable causes sas to set the wrong type. So: don't use proc import write a data step yourself.
Untested:
data work.scores;
infile "C:/mydir/scores_*.csv" delimiter= "|" firstobs= 2 missover;
length
number $14
dab rc construction flotte snt_col pre_col $ 1
activities $ 200
;
input number -- activities;
run;
If you want to see the real contents of a csv file, open it using a text editor, not Excel.