Using Shorter Thwart and Yoke ?

I recently replaced a thwart and yoke on a Royalex canoe. The canoe was in good shape but sat outside for a while and the handles, thwart and yoke needed to be replaced, I had a yoke on hand that was 2 or 3 " shorter so I just pulled the sides in and bolted it up. Would this of caused the center section of the canoe to bend in 1/2 or so. Or, is the likely culprit sitting outside in the sun?

Pulling gunwales in that much
Could indeed induce hogging a bit

I would never use a yoke or thwart…
that much shorter than the original, so I am guessing that created the problem. Not the sun

I have moved and replaced them on various canoes and always try to match the original

jack L