I am familiar with the current California law as I was responsible recently for arranging the open casket funeral for a colleague. We were told that there was no requirement but it was highly recommended as the body deteriorates very rapidly. A minimal embalming process was chosen. Even so my colleague look very different from his live body in that the tissue was bloated and the color of the skin was vey different. Having read the account of Mr. Rowe in detail, he clearly has indicated that body of Yogananda did not exhibit the normal changes that he was used to seeing.
I don't find Mike D. argument particularly convincing. He seems to imply that Mr. Rowe created a fictional account for some ulterior motive. Mr. Rowe in the complete letter speaks of what he saw in detail. Perhaps Mike's argument would be better served if he showed this detailed account to his experts. They would then have more information to decide whether or not the events described were unusual or not.