I have always been encouraged to pronounce the word, "vetin'ry" - with the "i" almost as a schwa.

"Coll-yi-ree" is pronounced "Dahn t'mine" round here! (or was until Maggie closed them all!)

I would favour " ar-bih-TREHR-ih-lee " as the real RP - "trahr" sounds a bit phony.