past simple in reported speech

Hi everybody, can you help me with the following, please?

In my grammar book I have:
‘That was the best ice cream soda I ever tasted’, which in reported speech becomes- according to the keys to exercises I have - He said that that was the best ice-cream soda he had ever tasted.

Another one is ‘That was a great game of golf’, which becomes He said that that had been a great game of golf.

I can’t see why in the first example was doesn’t go back to had been, as the general rule shows… Is there an exception to the rule?

I would have regressed ‘was’, too:

‘That was the best ice cream soda I ever tasted’
He said that that had been the best ice-cream soda he ever tasted.-- (No need to regress the verb dependent on the first past perfect if they occurred at the same time.)