I just want to point out that anything anyone says on the internet should be taken with a "huge grain of salt," but I will also add what Sal/ComicPop said that Spencer told them is so lacking in details that it could mean a lot of things. Cebulski has already admitted that Marvel Editorial had changed the ending (although he certainly made it seem like it wasn't a big deal, which again, can mean a lot of things).
Dan Slott stating that retconning One More Day was never on the table isn't mutually exclusive to the idea that Spencer's ending was changed by Marvel Editorial.
This is all grounds for why these behind the scenes conspiracy theories exist. But it doesn't necessarily mean anyone is outright lying.
It's that the Engagement Ring was brought back up at the start of Sinister War and then never referenced in any way again. It's conspiracy theory fuel.