So the solution after about a month of investigation was to do exactly what I was already doing, but to replace the version number of the block with that sixth field (well, not quite - you need to combine the mask, original version and sixth field together in a Boolean equation to get it right).
Good find, so it's "
Overt ASICBOOST" all along, it's just that the mentioned sixth field's value isn't exactly the version number itself.
I noticed that you only shared five fields in the OP excluding "
id" and "
method", others may find it confusing when reading your reply about the "
sixth field".
Snipped 1st field should be the 'worker', right?