When is an oak tree not an oak tree?

Your position condemns virtually all other English Bibles. The 'gross error' is NOT mine, but would be that of Jerome, Coverdale, Luther and many other translators that have rendered 'elah as "terebinth" or something else. According to your interpretation, any translation that did not have "teil" would then fall short of revealing God's whole truth. Your 'teil-equals-procure' claim condemns almost all non-English Bibles too; just two Spanish examples --

Pero aún quedará una décima parte en ella, y ésta volverá a ser consumida como el roble o la encina, cuyo tronco permanece cuando es cortado: la simiente santa será su tronco. (La Biblia de las Américas)

Pues aun quedará en ella una décima parte, y volverá, bien que habrá sido asolada: como el olmo y como el alcornoque, de los cuales en la tala queda el tronco, así será el tronco de ella la simiente santa. (La Biblia Reina-Valera)​

The Spanish word "roble" means oak, or a strong person ("encina" is a different variety of oak); "olmo" means elm (and "alcornoque" indicates yet another kind of oak). No tilia or linden tree references here. So, unless you construe and distort both "roble" & "olmo" into synonyms of 'procure' in Spanish then these Bibles do not contain the same teaching.

 

As mentioned in the OP the Hebrew word refers to the terebinth tree, but can be used as a proper name (which was irrelevent to the topic). Nothing was missed. 'Elah (Strong's #424 entry) is the terebinth and also the name of the valley where young David killed the Philistine giant; the same Hebrew word is used as a pesonal name (designated Strong's #425) of five persons: an Edomite chief, a king of Israel, the father of king Hoshea, a son of Caleb, and the son of Uzzi. This word derives from 'ayil (Strong's #352) meaning a ram, post/pillar, strong man, or mighty tree.

There is a completely different Aramaic word 'elahh (Strong's #426) corresponding to the Hebrew 'elowahh (Strong's #433) both meaning either a heathen god or the God of Israel. The word 'elahh occurs 95 times (all in Ezra & Daniel, with one possible exception in Jeremiah) and is rendered 79 times by the AV as "God" (capital-G), the rest as "god". The contexts indicate that this word refers to the one true God about 80% of the time, 20% false gods (0% trees).

Again, it seems you don't allow such trival things such as facts keep you from drawing your own conclusions.