Island in the Sea of Time - Why didn't they...

When the Islanders discover Smallpox in the part of the Middle East they were in, why didn't they send those infected (too late to save) on fast trading missions into the Walker ruled areas? That would have devastated his forces.

Yes it would suck for all the people there. But this was a fight for survival. I wouldn't do it in the 1632 world because a loss there, aside from the initial Croat calvary raid, was not a battle for survival. But in the IitSoT world Walker is a threat to survival.

And with the existing trade routes Smallpox was going to spread regardless. This just moved the timeline up a year or two.

Posted here as there does not seem to be a sub reddit for the series.