Thank you for the photos.
The dimensions are pretty close to correct, but when you fasten the wires to wood without any insulators there will be some signal loss. Also, a reflector on just one antenna would give at least as much gain as two antennas without reflectors.
How did you combine the two antennas, a splitter in reverse?
When you combine two antennas that have wire baluns, the is a 50% percent chance of getting it right, because the two antennas must be connected in phase to have any gain over just one.