I initially intended to put down $50,000 to get a sellers concession where they would cover closing costs and a 2-1 buy down (we have to put down 10% or more down for the seller to be allowed to give us that that amount concession, around 5.8% off the purchase price of $484,500, seller concessions are capped at 6% with a 10% or more DP).

In my experience, being around growth like minded individuals is what has allowed me to grow the most.

There's not a good reason to not ask for the allowed rent, the tenants portion generally is based on a percentage of their income not a percentage of rent. 

They only allow STR while you are in the home.

Doing it that way also allows you to get a general idea of how much income is needed to at least be close to breaking even. obviously being close to the break even line is not where anyone wants to be but it is interesting and useful metric.

The app doesn't allow rent by room, so I am sort of forcing it.

Unless those items are all satisfied (except for housing violations and some non-monetary liens which follow the property), the department of finance will not allow the deed to pass through to the next stop in the recording process.So even if you wanted to dump a property that was totally upside down with liens to someone who was willing to take it from you, you can't do it.

I think a kind reminder telling them that they are not allowed to use the agent or lender finder to solicit business and if they don't get it the first time, a simple temporary ban will help stop this. 

Then as you mentioned-- from there, I would network to absolutely find him a few mentors that would allow him to just shadow him.

Aim to rep seller but if they are unwilling to work with you, ask if they'd still be willing to allow you to shop the deal around to your buyers.