I think one of the four jokes is unidentified.
Suppose it was a joke about baseball.
I like names with different letters; we're OK here
if we use R for bRown and L for bLack.
Two first names are female (Ms.); two male (Mr.)
What I do is represent facts with lines:
Pos F.N L.N Jok Vamp
4 - - - -V
>x D G - -
x - - gam -
>y A/C R - -
y - - ugl -
- B - -vam -
z - - vam -
z+1 - - - V
1 - - - V
2 A - - -
3 B/D L - -
(I find this works better than cross-grid.)
It is immediately seen that joke #4 cannot be
game, ugly, or vampire, so must be baseball.
Soon everything falls into place:
#1 Carl White told ugly joke
#2 Alice Brown told vampire joke
#3 Bob Black told game show joke
#4 Dave Green told baseball joke.
White and Black are the vampires.
This puzzle was too easy.
James