@pslinn you wouldn't install the cert itself, your browser needs to trust the CA the certs came from.
If your browser is not trusting a ACME cert, then you need to look why your browser is not trusting lets encrypt. But what exactly is your browser saying about the cert?
For example not supply ownership doesn't mean the cert is not trusted.
thaterror.jpg
That specific error just means it not a extended validation cert, ie EV.. Googles ssl says the same thing ;)
google.jpg
You would have to find a site that is using an EV cert to see ownership info.. example here is one
EV.jpg
I find it highly unlikely that lets encrypt would supply such certs.. When you get such a cert, you have to jump through a bunch of hoops with the CA that issues the cert that you are company that you say you are, etc. And those certs are not cheap compared to just normal cert.
https://www.globalsign.com/en-in/ssl-information-center/what-is-an-extended-validation-certificate
Extended Validation Certificate Verification
During verification of an EV SSL Certificate, the owner of the website passes a thorough and globally standardized identity verification process (a set of vetting principles and policies ratified by the CA/Browser forum) to prove exclusive rights to use a domain, confirm its legal, operational and physical existence, and prove the entity has authorized the issuance of the certificate. This verified identity information is included within the certificate.
edit: here is an example of non trusted site, because I accessed it via ip/name that is not part of the CN or SAN listing for that cert
notsecure.jpg
If I look at the cert itself - I can see what CN and SANs attributed to that site that would allow for it to be trusted when accessed via one of those.
san.jpg
My browsers trust anything issued by my CA (home).. But since I was accessing it via something not listed in the cert, then the browser complains its not trusted.