I think there was two areas to reload with fluid... my instructions are not handy. Under a dome on top of engine? It has been a long time... cant recall... but the dynamo smoke is my favorite on this engine...
The main stack and whistle smoke unit is refilled through the stack; the dynamo has a separate fill hole under the removable dynamo piece. Interestingly, looking at the manual again just now, Lionel recommended 30-40 drops of smoke fluid in the main stack, which is quite a lot more than they did for later engines. When I took mine apart (see below) the whole arrangement of the dual smoke unit at the front looked odd with the divider in it and no obvious way of ensuring both smoke chambers on either side were properly filled with smoke fluid other than with very slow application using a needle dropper.
I was also reminded that there are separate smoke on/off switches for each smoke feature under the sand dome. Might be worth checking whether the whistle switch has somehow got turned off.
Otherwise this engine is not that hard to take apart but getting it back together without pinching any wires is a nightmare. I had mine apart when new because the stack smoke was lousy and the dynamo never worked as advertised. After a failed attempt at reassembly it went back to Lionel. Mike R. tuned it up as best he could but the whole experience put me off working on VL engines myself.