InfoPath Dev

So I am trying to do something to a SP list, after linking it inside an Access database, and I am coming across this problem whereby I am able to 1) add records in Access, 2) edit records in Access--UNLESS I go to SP online and populate the People fields in between 1 and 2. The second that I add People information (online, since I can't seem to do it in Access, even when I use the People integer value).......as soon as I've added People information online, then if I try to edit any record in Access, I get ""You cannot update this field because the value you're trying to apply is not valid or would break a data integrity rule. Please correct and try again." Researching this, it seems that Referential Integrity ONLY comes into play if you have actually created a Lookup-type column on your List Settings in the first place (which we have not). But my question is, I know that the person who created this list tends more to create cascading dropdowns (and maybe lookup-type functionalities?) inside Infopath, rather than using a Lookup column in the List Settings online. So....would it be possible that they've created, using the Infopath form design, some type of lookup dependency which is causing it to behave like Referential Integrity is set? Which might be leading to this error in some way? Is that even possible...

I did find a workaround to achieve my main goal, although not necessarily a direct understanding or cause of the problem as it manifested in my original post. Just figured it was good to add this information on in case someone else reads the post for their own help or to answer. I created a sharepoint VIEW, and then used access vba to link directly to the VIEW--this view contained none of the People fields. Once I did that, I was able to edit records on that view no problem, from Access. Very relieved.