I'd pick more than one option, actually. Timestamps works okay in most situations, and it seems to be the most common (both by votes and by my experience). But it's somewhat artificial. I agree absolutely that No Lynch being one of the tied 'votes' should trump the other target, as anyone else not voting is tacitly approving a No Lynch.
Ideally
I'd say lynch them both, as it's easy enough to deter people from trying that the first time they lynch a power role and a townie on D1...