There will not be 3 certificates here. There will be a max of two, and possibly just one with the second being a correction or alternation to the other. So technically, they have indexed all the records.
It looks like on GRO that the 1910 is tagged as an occasional copy which usually means there was some sort of formal alteration or correction made. You could get a digital copy for 3 quid which would help unravel exactly what was going on.