Do you think Christian told his pride about his estate in England, complete with human servants? Is that how he got those chicks to join his harem? Maybe he scared off the other males with threats of bagpipe concerts?
Seriously though, it's easy to believe that Christian would remember them, but any other lion, without prior human contact. would at least be wary, if not hostile.
That makes me wonder, who's the old guy with the stick? Maybe these lions are "wild", but in a reserve/sanctuary/park, where they do have some human contact? That would make a lot more sense, but I'm theorizing.