I’ve always been skeptical with the ‘asymptomatic’ claim.
Here are some studies:
A study on infectivity of asymptomatic SARS-CoV-2 carriers
https://pubmed.ncbi.nlm.nih.gov/32513410/
conclusion: the infectivity of some asymptomatic SARS-CoV-2 carriers might be weak
https://pubmed.ncbi.nlm.nih.gov/33219229/
There were no positive tests amongst 1,174 close contacts of asymptomatic cases.