That depends. Most countries have ratified the biological weapons treaty. If proven to be lab created, the onus will be on them/whoever to prove that this was not part of a weaponization effort. Not to mention, instant loss of goodwill across the world.
Personally, I think the idea of this being lab created by China is far fetched.
I suspect that it’s simpler than that. Having it accidentally leak out of a lab facility where it was being studied for legitimate scientific reasons would still be humiliating, and devastating to Chin’s soft-power.
Even if it was lab leaked... every country studies viruses it's a HUGE jump to conclude it was a weaponisation effort... The facility is next to one of their largest research universities NOT near its military research facilities.
Would China really do top secret illegal bio-weapons research in a lab essentially open to the public?
Personally, I think the idea of this being lab created by China is far fetched.