Additional info required on mail tokens
I am not sure if you are asking similar question to this one but my answer is the same so hopefully it helps you move forward.

Eileen did an extension that added some membership tokens to deal with contacts having multiple membership and which do work from 'contact'

{latestcurrentmembership.end_date}

{latestcurrentmembership.allend_date}

please let us know how you get on with it