who's with who (spoilers)
I'm inclined to take the view that Anthony Fielding the musician didn't have a career change to medicine and neither did his wife Rachel, and that the two of them existed only within Crossley's mind. Let's call the corresponding medics Hurt and York. From the look between Crossley and York en route to the cricket match (btw what's he doing out on a motorbike, presumably Robert Stephens'?) there seems to be something between them, which idea is reinforced by York rushing to the dead Crossley. On the other hand the curt "Bye" from Hurt to York suggests there isn't much between them. When he's about to bat, Hurt seems to be rather friendlier with the girl who Robert Graves encountered on the staircase ("Don't try and look up my skirt!"), and friendlier still when they leave the field together because of the rainstorm. So perhaps the staircase girl (Harriet?) became in Crossley's story the cobbler's wife.
Some of Crossley's words to Graves suggest a more radical possibility. When he says "That man had a wife who loved him..." he indicates Hurt. Graves asks "What happened?" and Crossley answers "He lost her," at he same time looking away, as Hurt scores a run.
In the film, Crossley goes on to say, "Every word of what I'm going to tell you is true. And yet I'm telling it in a different way. It's always the same story... but I change the sequence of events, I vary the climaxes a little..."
In the story "The Shout" by the real Robert Graves, the Crossley character says, "My story is true, every word of it. Or, when I say that my story is 'true', I mean at least that I am telling it in a new way. It is always the same story, but I sometimes vary the climax and even recast the characters..."
The script should not have omitted that last part, "I... even recast the characters".
Crossley in the scorers box sounds not so much like the man who seduced Rachel away from Anthony Fielding as a man who has lost the woman he loved (York) to another man (Hurt). In the recast version, the roles are reversed and Crossley triumphs over his adversary, at least until the end when everything starts to slip.
What about the final business with York and the necklace - are we to suppose that York removed a buckle by which Crossley had sought to regain her affections, perhaps with some success?
"I beseech ye in the bowels of Christ, think that ye may be mistaken."