I couldn’t find anything myself, so I fed the $result variable to a function that recursively printed all of the properties.
I’m going to guess that $_.ManagedItem.Name is what you’re looking for.
$_.Abort $_.Actions $_.ChallengeResponsePropagationSeconds $_.IsSuccess $_.ManagedItem $_.Message $_.Result $_.ManagedItem.CertificateId $_.ManagedItem.CertificatePath $_.ManagedItem.CertificatePreviousThumbprintHash $_.ManagedItem.CertificateRevoked $_.ManagedItem.CertificateThumbprintHash $_.ManagedItem.Comments $_.ManagedItem.CurrentOrderUri $_.ManagedItem.DateExpiry $_.ManagedItem.DateLastRenewalAttempt $_.ManagedItem.DateRenewed $_.ManagedItem.DateStart $_.ManagedItem.Deleted $_.ManagedItem.DomainOptions $_.ManagedItem.GroupId $_.ManagedItem.Health $_.ManagedItem.Id $_.ManagedItem.IncludeInAutoRenew $_.ManagedItem.InstanceId $_.ManagedItem.IsChanged $_.ManagedItem.ItemType $_.ManagedItem.LastRenewalStatus $_.ManagedItem.Name $_.ManagedItem.ParentId $_.ManagedItem.RenewalFailureCount $_.ManagedItem.RenewalFailureMessage $_.ManagedItem.RequestConfig $_.ManagedItem.ServerSiteId $_.ManagedItem.TargetHost $_.ManagedItem.DateExpiry {.NET DateTime object sub-properties...} $_.ManagedItem.DateLastRenewalAttempt {.NET DateTime object sub-properties...} $_.ManagedItem.DateRenewed {.NET DateTime object sub-properties...} $_.ManagedItem.DateStart {.NET DateTime object sub-properties...} $_.ManagedItem.DomainOptions.Domain $_.ManagedItem.DomainOptions.IsChanged $_.ManagedItem.DomainOptions.IsManualEntry $_.ManagedItem.DomainOptions.IsPrimaryDomain $_.ManagedItem.DomainOptions.IsSelected $_.ManagedItem.DomainOptions.Title $_.ManagedItem.Health.value__ $_.ManagedItem.ItemType.value__ $_.ManagedItem.LastRenewalStatus.value__ $_.ManagedItem.RequestConfig.AlwaysRecreateBindings $_.ManagedItem.RequestConfig.BindingIPAddress $_.ManagedItem.RequestConfig.BindingPort $_.ManagedItem.RequestConfig.BindingUseSNI $_.ManagedItem.RequestConfig.Challenges $_.ManagedItem.RequestConfig.ChallengeType $_.ManagedItem.RequestConfig.CSRKeyAlg $_.ManagedItem.RequestConfig.DeploymentBindingBlankHostname $_.ManagedItem.RequestConfig.DeploymentBindingMatchHostname $_.ManagedItem.RequestConfig.DeploymentBindingOption $_.ManagedItem.RequestConfig.DeploymentBindingReplacePrevious $_.ManagedItem.RequestConfig.DeploymentSiteOption $_.ManagedItem.RequestConfig.EnableFailureNotifications $_.ManagedItem.RequestConfig.IsChanged $_.ManagedItem.RequestConfig.PerformAutoConfig $_.ManagedItem.RequestConfig.PerformAutomatedCertBinding $_.ManagedItem.RequestConfig.PerformChallengeFileCopy $_.ManagedItem.RequestConfig.PerformExtensionlessConfigChecks $_.ManagedItem.RequestConfig.PerformTlsSniBindingConfigChecks $_.ManagedItem.RequestConfig.PostRequestPowerShellScript $_.ManagedItem.RequestConfig.PreRequestPowerShellScript $_.ManagedItem.RequestConfig.PrimaryDomain $_.ManagedItem.RequestConfig.SubjectAlternativeNames $_.ManagedItem.RequestConfig.WebhookContentBody $_.ManagedItem.RequestConfig.WebhookContentType $_.ManagedItem.RequestConfig.WebhookMethod $_.ManagedItem.RequestConfig.WebhookTrigger $_.ManagedItem.RequestConfig.WebhookUrl $_.ManagedItem.RequestConfig.WebsiteRootPath $_.ManagedItem.RequestConfig.Challenges.ChallengeCredentialKey $_.ManagedItem.RequestConfig.Challenges.ChallengeProvider $_.ManagedItem.RequestConfig.Challenges.ChallengeRootPath $_.ManagedItem.RequestConfig.Challenges.ChallengeType $_.ManagedItem.RequestConfig.Challenges.DomainMatch $_.ManagedItem.RequestConfig.Challenges.IsChanged $_.ManagedItem.RequestConfig.Challenges.Parameters $_.ManagedItem.RequestConfig.Challenges.ZoneId $_.ManagedItem.RequestConfig.DeploymentBindingOption.value__ $_.ManagedItem.RequestConfig.DeploymentSiteOption.value__