How much should we worry about the pneumonic plague lableak in Siberia?

Epistemic status: I wrote this up hoping people can poke holes in it because I am quite worried.

Here's what we've heard so far:

• Local media is reporting that an employee of a BSL-3 lab in Irkutsk, Russia, died of pneumonic plague on Oct 1st.
• The initial quarantine covered 200 people who were in contact with the employee before she died.
• The FSB (Russian FBI) was seen assisting in the quarantine, which means it was not voluntary.
• Soviet-era whistleblowers like Ken Alibek claim Irkutsk was a major bioweapon development facility.
  

As of Oct 4th:

• The quarantine has expanded to 5 hospitals in the area.
• The Russian government has switched to denial/coverup. Local news sources have deleted mentions of "pneumonic plague."

• Local universities and schools have canceled some classes and extended mask mandates.
• On the lab's website, they mention gain-of-function research for making bacteria more virulent.
• The White House is monitoring the suspected outbreak.

Why this might be a big deal

• Regular pneumonic plague is maybe not that hard to deal with (?) but if it is a bioweapon that was leaked, it could be significantly more virulent than, say, COVID. Pneumonic plague has an R0 of ~1.3-3.5, whereas genetically engineered variants could have an R0 of 5-12.
• If there is only one infection, then why quarantine 5 hospitals?
• If it wasn't a big deal, the Russian government wouldn't put much effort into covering it up. This is something I'll monitor over the coming few days.
• If this is a bioweapon, this could be quite bad. In Annie Jacobson's latest book, Biological War: A Scenario, much of the world is dead within the first few weeks after the first infection. I found it to be realistic, and it is a big reason I'm so worried. The scenario started basically identically to what's happening here.
• I asked the AIs if pneumonic plague is treatable with antibiotics, and they quoted me that the death rate with treatment is still between 8-30%.
• Soviet whistleblowers say they have successfully created recombinant plague with antibacterial resistance and much higher virulence, so we know it's possibly a bioweapon.

Why this might not be a big deal

• Some OSINT researchers looked at a bunch of street cams in Irkutsk and didn't find anything really out of the ordinary. Life is continuing basically as normal there.
• Nothing ever happens.
• We don't really have much info on the whole thing. There are no reported second cases from officials, but with historical evidence, we should assume a cover-up- e.g., the Sverdlovsk anthrax leak in 1979 and COVID-19 in China. So evidence that there are no secondary cases is not really (much) evidence.
• If it's not a bioweapon, it's most likely fine.
• Some smart bio people I know think this is not a big deal, but I don't really understand their reasons why.

Please let me know anything else I'm missing here.