Is there a way to possibly know if a respondents read or opened the email autoresponder sent to them after they successfully submitted the form?

Like what my colleague had mentioned from the other thread, there is no way we can do this within Jotform. That is why we recommend our users to hire a third-party developer to help them set this up as it is a bit technical.

Basically, what you need to know is if the image was loaded, whether completely or incompletely. Once you have captured the queries (the link/URL used to access the image), you will see the unique submission ID that was attached to its parameter (as explained by my colleague in the other thread) then you compare that with the submission IDs in your form.