the computer is owned by my employer, and they have a fairly long hardware refresh policy. They did state they will replace it if parts begin to fail or other hardware problems present themselves.
This reminds me of a Dilbert cartoon by Scott Adams...

TL;DR
Don't do this. It's not worth the risk to your career and could have legal ramifications.
One thing we were very aware of was a phenomenon called "gear envy." It happens and we know all about it. This is how you end up on the company's/manager's radar. Don't put your career in jeopardy because you don't know the level of technical skill your IT staff possesses. Also, bear in mind that IT will have spares at the ready and they are usually older, more beaten up models that you likely don't want to use.
My advice, given that these models can be prone to CPU throttling, is to document if/when this happens and articulate how this is hampering your productivity. Let it happen during an important PowerPoint presentation and you'll be issued new equipment with all due haste without relegating yourself to the dreaded "problem employee radar."
Since I do not want to wait another 3-5 years for an M-series laptop, what is the fastest way to "burn out" an otherwise fully functional Macbook Pro? I'm looking for non-obvious things like hitting it with a hammer or dropping it in water.
A non-obvious way to burn out a fully functional MacBook?
Det cord

"Burn the CPU"
Realistically, speaking, you're not going to be able damage a working MacBook (or any modern laptop for that matter) without physical destruction because these systems are designed, down to the processors themselves to shutdown long before damage occurs.
This is just a very abbreviated list of the types of questions asked here. The bottom line is even with all the heat related issues brought up on every platform from here, to Reddit, and even the official Apple discussion groups, when it comes to heat, the big problem is CPU throttling, not CPU death.
Water Damage
You could potentially damage your Mac by "accidentally" spilling liquid on it; I don't recommend this either. Acceptable Use Policies are usually written to hold the user accountable in cases of negligence. I can't speak for your employer, but all of the AUPs I've written included clauses for due/reasonable care.
Maybe you get away with it, but I can tell you from a management perspective, you'll be on someone's radar. Maybe it's your direct supervisor or the IT manager. Either way, it's not worth it and I don't recommend it.
You could acquire a USB device that is basically nothing but a capacitor that discharges high voltage on the data lines effectively killing the USB controller on the logic board.
The problem here is that it only fries the USB chip and on a MacBook Pro from that vintage; there's two - one on each side of the logic board. So, you'll end up with two conditions:
- kill ony one port and you'll be left with a fully functional Mac minus ports on one side.
- kill both and you end up on that radar I mentioned earlier because doing this once can be explained as "an accident." Two times will bring your judgement into question. "It fried one port so I just pluged it into the other" is a statement not likely to fly.
Since it's just a USB port that gets fried, likely your machine will be repaird under AppleCare and returned to you. You can also be told to "just use the working ports."