they are the same meaning .but express the differnt emotion .
果然。。 express : what happen is just as expected .
for example : 他果然迟到了! ”he is late as expcted " (before he is late you think he would lae , the fact is he is late )
真 ,just is a truth .
他 真迟到了。 he is late ,(this is a truth .)
确实:make sure about the event again.
他确实迟到了。 it meaning ,somebody make sure he is really late ( for example , the meeting is 6 ;00 pm ,but he came at 6:10.. after you check the time, then you said " 他确实迟到了,现在是6:10.)
实在 use to emphasize the result, the event ,or the mood .
他 实在太晚了。“ he is really toooo late "
他实在太好了." He is really sooo nice .”