I wouldn't get too hung up on the low level components in a handheld XRF test. These units use an algorithm that measures the energy level of of an excited electron as it is hit with an Xray. There is a lot of overlap in multicomponent materials, which makes it difficult to be confident of the low level elements. Unless you run a Gage R&R or some other statistical analysis on the sample, I would tend to ignore the Pt an Ga values that the OP reported. There's a reason why handheld units are a lot cheaper than those in a research labs and why the results from a trained technician are more accurate than some guy in a "We buy gold" place. That being said, I feel confident that the quarter is primarily tin and lead based on the the handheld results, but do I believe it to a 1/10th of a percent as per the reported comp? No way.
I don't believe there is any platinum in this coin. I am just saying, you aren't putting $1.42 worth of platinum in a .25 cent fake coin. Even if the coin is old, the platinum spot then, is still worth more than the coin.
43.3% lead? I'd think with it nearly half lead it would weigh much more than what is being claimed it weighs.
What I want to know is whether rascal ever quoted paddyman again over the following year. This is good stuff. We need a popcorn emoticon.