Can a bad switch box cause one wire not to spark

[steplift20]

Thanks spare
I'm getting two new ones tomorrow , someone told me it could be the trigger but I don't know how to replace the trigger assembly
This is what I did so far
Replaced the coil with one I know works, ( still no spark)
Replaced all the ignition wires
Next I'm going to replace the 2 switch boxes after that I don't know what my next move will be
The one thing I noticed it that the wire with no spark did have a spark but it only sparked a few times and very spaced out then nothing I'm using a spark tool from harbor freight
I checked out the other wires and they all test good just not the bottom one on the starboard side
I will definitely let you know how it turns out with the new switch boxes
Thanks spare.
And the weird thing is it's only running on five cylinders and the motor sounds great no miss so I'm wondering how long it's been like that.