I have a 32-bar song with a 4-bar intro and a 4-bar ending. The song has 2 choruses. I wanted to print a chord lead sheet of just one chorus showing both the intro and the ending.

When I select first chorus, it prints the intro but not the ending. When I select last chorus, it prints the ending but not the intro.

It appears you need to check "whole song" to get both, but that prints the chorus twice.

The ending is a coda that is played only after the last chorus. Ideally, it should print with proper coda markings.

So I would suggest adding some check boxes for "print intro" "print ending" "mark ending as a coda" or something like that.

If it doesn't exist, and it might knowing the weirdness of BIA, just go back to basics.
Take a copy of your song under another name and delete everything that you don't want to see
Print the result and discard to temporary song.

Not everything has to have a technical solution