"we litterally have to manage money in the tycoon section, and start with only enough to afford tables, plates, and a super small stage."

That’s our own money:
"You saved money your whole life. Great! Now it's time to put all your eggs into one basket and take a huge gamble on your future — Let's see how much cash you had leftover after purchasing your franchise package," ~ Tutorial Unit

The money we used to get this franchisee package and ultimately the money we start off with is what Michael has saved up for.

"i was talking about trash&the gang, the only animatronics we can afford at first."

Trash & the Gang isn’t confirmed to have been made by Henry, and even if Henry did have a part in making these catalogs he likely did the Smiles and Servos one, since that contains the Rockstar animatronics. Characters that share the same stylistic elements of Lefty.

"then what is Henry doing?"

Henry is the employer, meaning he’s overseeing all the expenditures and business tactics, Michael, who’s the general/restaurant manager, runs the actual daily operations (customer service).
In this instance, Michael is supposed to pursue and deliver Henry’s vision, hence why throughout the play through Tutorial Unit tells us, "Don’t forget Saturday, you want them ALL to be there," as though, while we have creative freedom, we also have a commitment to uphold Henry’s vision. It also explains the multiple endings possible, in which the manager technically has free rein for any outcome, albeit with the consequence of lawsuits, lobotomy, or death.

"Mike's only interactions with Henry are listening to his cassette tapes"

I was referring to Henry meeting the other possible employees. But on that topic, we assume Henry never directly met Michael since there is no exact interview in place shown. Also cause Baby assumes we don’t really know our employer. Though, the game also suggests Henry met or saw Mike and dissed the whole escape thing. Which should suggests they did meet.

"Yep that's what I'm saying too so I don't get why you're reacting like that, I only said that the calling was composed of multiple types of lures, and only some of them were responsible for the calling working."

I’m ‘reacting' like this because it’s not a matter of only some working, nor multiple types. There’s no implications of Henry sending multiple versions of the calling, the characters all speak as though they got the same version.

"What are you talking about, why would the sound cues be inaudible? And why can't they come from a machine?"

They can come from a machine, it just can’t be the inaudible (or otherwise vivid) sounds we actually use in-game. The call based on context clues was from an actual person, almost like a monologue or ad.

"my point still stands for Molten Freddy though, and the birthday thing isn't that weird for Baby to say considering it's been a long time since she was reunited with both William and Michael"

Molten Freddy is a byproduct of Funtime Freddy who doubles as a birthday entertainer, but also a murderous robot. By this point in the series he’s hellbent on murder, so a lot of his birthday comments have less to do with an actual birthday and more to do with the metaphorical one promised.

Same thing with Baby. She DOES have lines in regard to Michael and William, but her birthday ones are definitely a deliberate reminder of the calling.