Not sure how did that happen, but I have a tame vole that is encased in abyssalite and a jet suiter in intact natural tile pocket.
Pretty sure both of those happened when the terrain nearby was changing in some way. In case of vole, it was probably meteors, while jet suit either got bugged due to nearby dupes digging or due to water shower disabling jetting.
Steps to Reproduce
Status: Known Issue
We are aware of this issue and have it logged internally but either we do not have a fix ready yet or we are not planning on addressing the issue in the immediate future.