is this a voidable contract?

[hexeliebe]

Shaun;

Take the advice offered and stick with the "EXACT" facts of the case. If the professor comes back and asks a "What-if" question your response is "The law doesn't deal with What-if. It deals in proveable facts. And the facts of the case, as outlined by you (the professor) are these". List the facts then present the argument that IAAL offered.

It sounds like you are trying to please the professor instead of find the correct answer. And that's always a pit you can't get out of.

 

[drago]

Some ideas

I think that undue influence could be argued because she agreed but failed to perform
so as not to harm her image.

This could also be considered a frivolous contract that a reasonable man would not see as valid. In theory, harmony is a desirable element in a contract

She could pay for the tire change the next day in cash.

You are not being asked for a verdict. Only to analyze the legal
aspects of the slippery situation