No I read a forum on Rockstar website they have automated sweeps and so it checks for illegitimate transaction and shit like that so private lobbies won't really work. Like if you spawned like 18 million cash in small period the system will pick that up and it will ban you or alert rockstar so they can ban you.
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https://support****ckstargames.com/hc/en-us/articles/201142806-Clarification-about-being-banned-for-gifting-receiving-modded-money and on the website there it says
"To keep the gameplay environment as fair as possible for legitimate players, we routinely do sweeps to separate out cheaters and modders, and to reverse any illegitimate transactions. These sweeps are based on in-game automated detection, examination of suspicious gameplay statistics, and also manually-reviewed evidence submitted by the Community."
Also my previous reply they may not ban you right away but they will reverse it but there still is a chance of getting banned.