They merged the raws which are split by panels to load faster on mobiles and slower connections into big pages meaning they had prior scanlation knowledge of a group that uses those same softwares to merge.
They used scanlation fonts which by itself isn't that big of a deal but when you add it all together it makes sense.
They used actual manga terms, and in comments in forums knew about every single monetary way of earning while scanlating and used it to try to prove it wasn't a snipe (which was wrong)
They sniped this series in specific.
Meraki itself has caused a lot of people to be upset by how honest and upfront they are about their beliefs. This includes certain translators who left while being upset due to overall retarded reasons such as jelously of other of their series which got released more often, and other stuff like that
Just recently meraki was involved in taking down a big group called trash scans which may not be involved but gives reason to doubt (that trash scans group was lying and claiming to have licenses amongst other stuff in order to steal series from other scanlators and threaten said groups)
They also made sure to include that said "out of boredom excuse" to try to get people to not connect him to any group
All the sniper's accounts are brand new, made yesterday (reddit and mangadex) meaning they're obviously alt accounts (what could someone "doing it out of boredom" be hiding...)