The accrued interest, late fees, foreclose fees/costs, plus the sales cost would eat most if not all of any equity potential in my opinion.No short sale here either based on what you wrote.

My plan was to use that as a “savings” and have it accrue better interest, until one day I can go on an investing spree in real estate.

When you sell, or refi, you will pay owe your PML $50k + any accrued interest for that month, i.e. you sell on 15th you owe $104.17.

Meanwhile the holding costs will be accruing and you'll bleed to death financially.

Mortgage interest (also known as per diem interest) that accrues between the closing date and month-endIf you're unsure about whether a certain item is included in closing costs or prepaid, just ask yourself a simple question: "Is this a charge that I would have if I wasn't borrowing to buy the house?" 

It's important to note, that most syndication structures will call for distributions to accrue.

Also adding $6k attorney fees accrued since 2/2020 judgment.

—During a period of forbearance described in this subsection, no fees, penalties, or interest beyond the amounts scheduled or calculated as if the borrower made all contractual payments on time and in full under the terms of the mortgage contract, shall accrue on the borrower’s account."

Does it accrue monthly or yearly?

The interest accrues over time and I can pay back the principle or interest whenever I want.