I can't account for Canadian tone deafness, but unlike most English terms, industry terms (especially obscure industries) tend to have a lot of consistency in pronunciation, probably because it isn't open to the sort of evolution of words that happens with wide exposure.

So if you invent a term, you get to set the pronunciation, RANK /CINTEL ( Rank was a british company) invented the telecine in the late 30s, (kinescopes were used before that) so probably the name came from an Englishman which would explain the telly part.

As for using the pronunciation of the last syllable as 'seen' it is far too close to 'scene' for me, tell a scene would probably cause endless 'who's on first' type discussions.

Whatever way you slice it, like most industry terms (and unlike most common language) there is a correct pronunciation and it seems consistent between English speaking countries.

Now who is up for the correct way to pronounce kinescope?