Do you have a Dell account where you can still download the iDARC 4.3 module? You may have to manually add the component before the image creation.
I would also check through Dell support what compatibility their iDRAC series have against VMware versions. Look at it from both sides to see if there is a path.
You may also have to consider that the older Dell servers may need to be classified a different way due to potential conflicts in compatibility of the different software components.