Unobtainable Achievements On Xbox(Windows 10 Edition).

Those achievements have been known to been buggy. I've had a similar issue and on a few achievement hunting forums such as the previously mentioned TrueAchievements website, there have been quite a few people complaining about certain achievements from this
last update not syncing/unlocking at all. Its effected console, mobile, and PC. I'd recommend going tp the Minecraft forums or on Mojang's/Minecraft's website and make a post about it as well.

https://www.minecraftforum.net/

I have checked both the achievements on their True Achievements pages, and no one has mentioned either one being buggy. And if an achievement is bugged its usually mentioned in the comments or forum. Here's a link to their Minecraft Win 10 forum if you
want to check that out? It's a great place for help with all achievement issues. Hope it helps.

TA Minecraft Windows 10 Forum

Hello there!

The achievements are unlocked when certains conditions are accomplished. Usually, this means that the game has a inside counter that when reach a certain number, changes the 0 to 1, (false, to true). So, my recommendation is, try watching YouTube videos
when some player is unlocking the achievement, and try to recreate the environment and conditions.

What about paying for leaderboard achievements. I know for a fact this one clown [Mod Edit] has paid others to get otherwise totally unobtainable achievements from losers that block leaderboards in games like Kane & Lynch for profit

No they are technically two different games, Minecraft Windows 10 edition for example I have achievements from Windows 10 xbox switch and mobile versions of the game it is intended and not a bug just enjoy your Gamerscore.