I'm sorry, I come online once a day and if the user is online at the same time, I may exchange some posts during that session, but if there's nothing new before I go offline, then it'll be until next day that I see any new replies.
About the email, got it. When you said "welcome email" earlier, I thought you were talking about the New User one, but I see now that that was working fine, you were talking about the one you send from AWeber. Since the custom New User email was working fine, you can change it back.
About the restricted page, when I tried to load it I got properly sent to your Membership Options page and the vars at the end of the URL show that it is restricted at Level 1, so Level 0 (free) or non-logged in users won't be allowed to load it.
http://hecoa.com/join-hecoa?s2member_seeking=page-743&s2member_level_req=1
About the AWeber log, check the
/wp-content/plugins/s2member-logs/ directory using an FTP client like FileZilla, or the file manager in your cPanel (if you have that). Do you see a log for AWeber there? If so, do you see entries at the end that belong to users who didn't get the confirmation email? If so, please post them here x'ing out private info.
By the way, did you ask the user to check the spam folder to make sure the AWeber confirmation email isn't there?
You said the AWeber integration was working until recently. Could you check if your AWeber settings are still correct? I don't know what could have changed them, but it's fine to double-check.
WP Admin -> s2Member -> API / List Servers -> AWeber