Looking for basic mindsets and strategy tips for such games description below.

The basic format is starting with 1-2-5 game with tons of straddle (1K buyin). After about 4 hours with they raise the blinds to 2-5-10.
Still tons for straddle and the buyin increases to 2K. 10-Max often full ring.

Rake structure is absolute disaster. They say the max is kept at $50 official but tend to take 10%+ at every pot. I've seen and experience dealers take $120~$150 if the pot
goes over to 2~3K. Rake is something I cannot raise my voice about in this game due to relationships with the managers and etc.

The rake is then used for payback to players who lost alot depending on their losing size. Typical 10%~20%. 20% occasionally. ex) 10K loss results in 2K return so 8K loss overall.

Players are very fishy with some tight passive but mostly loose players splashing all around.
Huge VIP come quite often 1~2 times a week. The game becomes insane as I've seen loses over 20K.
1~2 regs are present but skillwise they are not much of a concern.

I have very good relationships with house managers so I have some negotiation availiable concerning buyins and rake back.

The only way I believe I can beat this game is to play exteremly tight preflop and enter pots with large raise sizes. Is there any other tips with this strucutured game?
Some regs which I know for a fact that they are winning players say that the game is impossible to beat long run due to rake even if the pool is fishy.

That's the right strategy if rake is capped at $50. If it's in fact uncapped at 10%, it doesn't really matter.

Is there preflop rake or do they have a "no flop, no drop" policy? If the latter, try to win pots preflop.

In a regular setting, players have to be insanely bad to beat that rake. With "rakeback" to the bigger losers, it depends on how much they get back and what percentage of that stays in the game.

Sounds like Cambodia!

These type games are fishy enough to beat imo, but yeah don’t go splashing around in every pot with mid strength type hands. People hate folding preflop so size up those preflop raises and 3 bets! If you’re getting called wide on the turn sometimes you’ve just gotta fire all 3 streets as a bluff when you get a good runout for your range. Rakeback for the losers sounds interesting

In my limited opinion, any game that rakes 10% uncapped isn't beatable and again, in my opinion, any game that is raking that much is also likely doing other shady things.

As for the strategy, if it's a 10% uncapped rake game then we do have to tighten our range preflop as certain hands lose their profitability however playing with big raises no longer makes sense from a rake avoidance pov without a rake cap as we raise big in order to reach the rake cap quicker, here there's no cap.

I can't stress enough how much I feel these types of games aren't beatable long term

It depends on how terrible the players are. There is a line where the game is profitable/isn't profitable. With terrible whales just dumping huge amounts of cash, the game is beatable. If they're just regular bad players, then maybe not.