My only comment is that on my allotment that I have had for 8 years now I have always added horse manure every Autumn and slowly over the Winter it has reduced down.
Whether that is due to the worms or just gravity or the weather is debatable.
I have used 3 different suppliers of manure and one lot of bags had the red brandling worms trying to escape from the tops.
I put all my coffee grains out on the garden and the worms love it,there are always more underneath them than anywhere else in the garden. (clay alkaline soil)
The whole truth is an instrument that can only be played by an expert.
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Whether that is due to the worms or just gravity or the weather is debatable.
I have used 3 different suppliers of manure and one lot of bags had the red brandling worms trying to escape from the tops.
https://www.greenandvibrant.com/types-of-earthworms
Why not try some horse manure .
Where I live the cost is between £3 to £4 a bag which will cover an area of 1 x 3 foot of soil.
As Allotment Boy says give it a go but note the results
I follow No Dig so leave all of the worm motorways in tact.