Just like the scenario description says, “This is your biggest challenge yet”, and indeed, it’s quite a difficult scenario. It’s a bit like a combination of Mountain Spring and Mine Mountain regarding the objectives. If you completed Mountain Spring before (completing Mine Mountain is a pre-requirement of unlocking this scenario anyway) that could help a bit, too.
First of all, you have a huge plot of land, but with a pretty bad placement. There are relatively large flat areas at the sides, but they’re too far yet from the “main building” so trying to connect them with a path to the center would be a suicidal move at the start, because the path would eat up all your money.
Rather, build some flat rides near the main building (a Top Spin could be a really good choice for example, an Odyssey Ride as well) as well as some food, drink, souvenir stalls and facilities. Try to aim with the path toward the closer of the areas. Also, try to avoid cutting down trees as it will cost you a lot and you wouldn’t want to waste your money on that. A nice source of profit could be to build a coaster now. I built a Reverse Freefall Coaster for its compact nature in the center of the enclosed area. Any coasters should be fine, too, just have a high excitement rate so you can ask for adequate ticket prices. Build more flat rides on one side of the separated area and leave the other side free for an enclosure. As soon as you have a decent monthly ride income, build an enclosure at the mentioned area. I built a wooden fence enclosure with ostriches and zebras and raised the ticket prices of the viewing galleries to 200%-250% of the initial $1.00. If there are enough and interesting animals, the guests will pay it. Don't forget to pay attention to the thoughts at every viewing galleries, however, if you see the guests thinking “I won’t pay this much for it” then lower the price until they agree with it. This is quite important, because you need a ridiculously high total monthly viewing gallery income for the tycoon goal, so you both need to ask for high prices, but just as high as the guests will actually pay, instead turning back. Try to build a path connecting the horses enclosure (also note the three horses the park from the start are all males, so if you want more horses, buy some female ones, too). As well, build some viewing galleries there and some more rides along this path (and price them), and you should pass the apprentice level.
For the entrepreneur, build more flat rides and enclosures with animals and price them just like before. A great means to earn a good, steady income is to build some transportation ride (I built a Hop-on Hop-off Transport Trams) connecting the enclosed area and the main building, or alternatively, encircling the park, with several stations. It will cost a ton of money to build, but it will pay off nicely. Needless to say, price this as well. This also should be a great means to connect the big flat areas on both sides into the flow of the park. If you have enough money, try to connect these areas with a direct path to the park, too. Build more rides (including a coaster if you want) and more enclosures with animals, price them, and you should eventually pass entrepreneur. Also, note that this scenario has quite some awards with nice cash prizes - but it also has quite some fines, too, which could hurt a bit.
The challenge comes now! The objectives of tycoon are just ridiculous. The park value shouldn’t be much of a problem, but squeezing out the required amount of monthly ride and viewing gallery incomes will not be easy. You need a ridiculous amount of enclosures with all sorts of animals, as well as it’s advised to have thrill rides near the enclosures to attract guests there. It will be tough, but at least you likely don’t need to worry about your finances anymore at this point, because your monthly total profit should be huge. For the ride income objective, build even more flat rides and coasters (ensure they’re maintained by mechanics and priced). I “summoned” some of my best coasters from other scenarios here but… You should notice that, likely, barely any people loiter around the queues of your rides. The reason is nothing else than your other objective, as nearly all the people go to the viewing galleries (despite that, it seems like barely anyone uses them, but that’s probably just because the ridiculous amount of viewing galleries you should have by this time). Doing some marketing campaigns now should be a good idea, too.
This will be a downhill, a final great struggle, to try to squeeze the required amount of monthly profit from your viewing galleries. It’s not easy, but it can be done. Marketing campaigns could help a lot. Once you see the checkmark at the monthly viewing gallery income objective, shut down all of your viewing galleries at once. You should notice that your ride queues slowly get filled with crowds again, and if you have enough flat rides and coasters (and with good ticket prices) you should complete the monthly ride income objective in the next month or two.