Leaving the Anabella by car requires you to turn right on Katella then do a u-turn and come back to make the right turn onto the road that PPH and the Grand are on. Unless you met the taxi on the West St side of Tiffy's restaurant and the taxi was headed in that direction already, you cannot do the shorter route goldmay showed by car.
Taxis I've been in in Anaheim are mileage AND waiting time. Get some traffic while waiting to get out of Anabella, some traffic when waiting to u-turn, and traffic waiting to turn right, and that meter is ticking.
I would plan on $20 and rejoice when it's lower.
If you walk, you go out of Anabella to the left, cross the (longest) crosswalk (in the world, LOL), and walk on up the street. Very very pretty street, with weird curves in it. If you look at a satellite view of the road you'll see that the weird curves are part of half of a giant hidden Mickey.

Lovely trees, birds of paradise flowers, etc. If you have rolling suitcases it shouldn't be too hard.