ttr: You shouldn't be stressed re confusion between Rhymer & Tam Lin. There are many similar elements and cross-over is not unusual. Amusingly, the only version I've found so far this weekend from the N.E. of Scotland is called "True Tammas" but is absolutely a pretty full version of "Tam Lin" with no cross-over from the other at all!

Toad: Thomas is receiving the gift of prophacy but he has the ability to use it or not as he chooses. He can still lie when he chooses.

It may not be such a jump between the bad apples - noting that the fruit of the Tree of Knowledge was fatal (Adam & Eve die) and the "poisoned" apple is also fatal.

Yiz may wish to have a look at Oral footnotes