Class setQueue does not exist. Invoice not emailing.

I am self hosting 4.5.8
I have only found this error appearing for one client so far. It appears on the edit invoice screen beside the ‘View In Portal’ Link under the user’s name. Other clients show a green circle and info regarding when sent and viewed. On this client is shows the red triangle with text ‘class setQueue does not exist’
When trying to send email I am receiving confirmation in invoice ninja that email was sent however they are not going through my SMTP server and of course the client is not receiving message and I am not receiving the BCC. I have had no issues sending and receiving invoices in the past with this client.

Recent laravel-error.log entries
[2019-01-13 22:17:47] production.ERROR: ‘logout’ is not defined {“context”:“JavaScript”,“user_id”:1,“account_id”:1,“user_name”:“MY NAME”,“method”:“GET”,“user_agent”:“Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36 Edge/17.17134”,“locale”:“en”,“ip”:"##.##.##.##",“count”:1,“is_console”:“no”,“is_api”:“no”,“db_server”:“mysql”,“url”:“log_error”} []
[2019-01-14 13:27:29] production.ERROR: Class setQueue does not exist {“context”:“PHP”,“user_id”:0,“account_id”:0,“user_name”:"",“method”:“POST”,“user_agent”:“Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0”,“locale”:“en”,“ip”:"##.##.##.##",“count”:1,“is_console”:“no”,“is_api”:“no”,“db_server”:“mysql”,“url”:“payment/koaieppkertjuxy4kcmfvpd3lrlxxxxxx”} []
[2019-01-14 13:27:29] production.ERROR: Class setQueue does not exist {“context”:“PHP”,“user_id”:0,“account_id”:0,“user_name”:"",“method”:“POST”,“user_agent”:“Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0”,“locale”:“en”,“ip”:"##.##.##.##",“count”:2,“is_console”:“no”,“is_api”:“no”,“db_server”:“mysql”,“url”:“payment/koaieppkertjuxy4kcmfvpd3lrlxxxxxx”} []

Which version of PHP are you using?

https://stackoverflow.com/a/53863955/497368

It is running PHP 7.3.
I just changed PHP to 7.2, 7.1, and 7.0 with no luck in correcting the error.

This appears to only be an issue with specific clients and isn’t site wide.