Its all possible depending on how much risk you're wanting to accept/life constraints you may have. 

In order to to do so I'd have to forgo multiple months of rent until it gets resolved (you can't evict and accept rent) and there isn't even a strong guarantee that I would win (CA is a tenant-siding state).

(Owner occupied financing (less than 20% down), investment (20% or more).Having your conditions to close on a property laid outWhat's acceptable cash flow?

I would talk with the agent and come to an acceptable agreement. 

In other words, you submit an offer and it is accepted, but you can't find a partner or way to actually pay the downpayment and rehab costs.

Would it be acceptable if the partner doing most of the work contributed less or potentially nothing and still split the profits equally?

Keep in mind that even if the insurance company is willing to accept the liability, you may get very little back.

Most owners will not accept an FHA contract if they have tenants in place (if they know anything about the FHA buying process). 

Let her know that this is your property and it being unclean and not maintained is unacceptable to you, a violation of the lease, and you don't care if in her culture this is acceptable.

I tend to buy in the Southern half of the US for 2 reasons:1) you get much higher year-round occupancy rates in the South & it’s simply tough to earn a good ROI in the North if your place sits vacant for a big chunk of the year2) Culturally, the Southern half of the US seems to be a lot more accepting of STRs regulation-wise.