As an alternative, would a cash-out refinance, a home equity loan, or a HELOC make sense for you?

Things have to go really bad from here, as I see it, for the office to underperform alternatives in the next few years, from a cash flow perspective. 

I would not invest in real estate with a retirement account.Its too much of a headache and likely not that much better as an investment alternative within a retirement account1) Real Estate provides tax benefits for individuals who own them.

Therefore, I have a hard time committing to a house hack which contributes greatly to my problem of raising capital for a conventional mortgage with a 20%+ down payment instead of alternatives such as an FHA. 

Alternative options include offering a significant down payment, a lease-option agreement, a joint venture, or a deferred closing to align with John's timeline.

If managing the STR is no longer sustainable @Robbie Shiver, here are a few alternative options to explore:Mid-Term Rentals: Consider marketing to travel nurses or corporate relocations for stays of 1-6 months.

Because your alternative is zero income.

. ;-)  While I wait for delayed communication from them, I am looking for alternate management in the Canton area. 

If this isn't an attractive alternative to your business partner then you might consider changing the ownership structure or operating agreement as one of your options.

I'm not sure how fast you want to scale, but I see that as a feasible alternative if you don't want to go through the process of either BRRRing or the fix and flip.