Lyme's incubation is long and impact on infected people uncertain, which makes it useless as a bioweapon. The sciencedirect article effectively dismantles the innuendo about Lyme as a bioweapon.
a weapon released without a means to target and control damage is generally less effective than one you can make sure isn't pointed at your feet.
lyme disease 'immunity' is spotty at best, and not well correlated to a specific group of people or traits; so while I could imagine its' use as a weapon, it seems that from a military strategy point of view that there should be better options.
there are plenty of diseases out there with what seems to be a racial component to immunology, I would imagine those are the ones with a lot of bio weapons interest towards them.
So why use timers on bombs then or have land mines, why not just kill immediately?
So bioweapons with an incubation period are still valid and makes it hard to prove who is behind it, and plausible deniability is a form of stealth bio weaponry.
If I put a tick carrying this bio weapon strain in your coat at a conference, you would not know it was me, because of the incubation period, assuming a 100% infection rate, just like you probably wouldnt check your coat for ticks before putting it on.
So why wouldnt it be anything other than a bio weapon, if it was man made and used in such circumstances? The only people probably safe from such risk of it being used against them would be scientists who could come up with a solution or cure, if one doesnt already exist.