I think a lot of this stuff about career omission is overrated. Greatness is proof you can win on all surfaces. Certainly Rosewall and Gonzalez could win a high percentage of the time on any grass surface and I am almost certain they would have won many Wimbledon titles if they were allowed to.
Borg was a great fast hard court player and I'm sure he would have won a few US Opens if not for some bad luck and retiring early. It doesn't take away from the fact he could also win a great percentage of the time on any type of hard court.
Laver was a great indoor player and not winning WCT is not a negative in my book against him.
Most of these greats could win a very high percentage of the time on any surface. There are some exceptions of course but I think we all know them.