I'm pretty good at web server administration but I still don't see how I could point a url to a subdomain and have the URL activate a survey on that sub-domain unless LS is installed on that sub-domain.

Unless. . . you are saying subdomain.mytlddomain.com points to a URL in mytlddomain.com - is that what you are suggesting?

Via different configurations on the webserver you can point a subdomain to any other URL you want.

you can point your subdomain survey1.yourdomain.tld to the actual survey URL yourdomain.tld/index.php/599791. Or redirect it.

Because the important part is that it is easy for your respondents to type in the URL, the rest doesn't matter much. They either don't even notice the redirect or the mostly don't care.

Important is that you make it as easy as possible for them to type the URL and then to type the token.

Thank you. I did as you suggested by creating a sub domain and then pointing the link to that sub domain which further points to the actual survey.

That is ingenious and I thank you for that valuable tip!