To navigate the nuance in the laws properly for compliance and to accurately structure our LLC, I am looking to consult with an attorney who knows immigration + business + tax laws. 

Make an informed decision if you think people are properly trained?

Like Jake Baker suggested, keep good records and have a dedicated bank account for your property, properly separating personal and business expenses.

But keep in mind if your using money you cant afford to get back then buying action property might not be appropriate for your current endeavors and its better to just buy open market were you can do proper due diligence and know you have a build-able site.

It also will help you a lot to learn how to properly calculate ARV as your buyers will want to work with those wholesalers more than one who is just throwing properties at them.

It sounds like the proper expectations weren't set when you took them on.

Can anyone recommend software which would accept monthly payments (from me to seller) and create proper 1099 forms for tax purposes at year end? 

With that comes different exposures and risks that they need to properly rate for.

this is what Oregon has done starting in July to regulate  the wholesaling activityhttps://www.oregon.gov/rea/newsroom/Pages/2024-OREN-J/Proper...  

I don't believe you would properly replace the debt in this situation.