No, if the facts of loss occurred just as you described them, you wouldn't be considered at fault. The key here is the lead vehicle driver's statement. Specifically, did he/she feel one impact (from your car being pushed into his), or did he feel two impacts (which would indicate you rear-ended the lead vehicle first, and then you in turn were rear-ended). But, just because your car made contact with the lead vehicle doesn't mean you're automatically at-fault.
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