Marquis and Count vladimir were among the random-splash art projects.
Basically when they started the skin splash art update they picked skins based on personal preference,so the process was pretty random(this is why we got for example vandal brand and jade dragon wukong),but then they started to focus on the visually updated champs.
However even though visually updated champs are their priority now,they still have a bunch of half finished splash arts lying around from the time where the process was unorganized and these splash arts get finished from time to time,so that they aren't wasted.So Count and Marquis vladimir were only done because a rioter picked them up during the unorganized process.
But nowadays these random updates are getting rarer,which makes sense as they likely finished most of the partially finished splash arts.And i doubt that they have plans for Blood lord vladimir,otherwise they would have likely bundled him with the other 2 Vladimir splash arts.