I have to admit that I didn't actually know what a syncopated vowel was, but I had a quick read-up on it. If I'm reading it correctly, it's where a vowel can be unpronounced given certain criteria. If that's the case, then "Pamela" would indeed fit that description.
It is quite frequently pronounced "Pamla", certainly in the part of the UK where I live.
If I have completely misunderstood the point, then apologies.
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