You never did reply to the suggestions you were given.
Did you do anything with them and test temperatures and memory?
It sounds like you know it's a temperature problem.
If you do any cleaning without knowing the current temperatures, you will not know what difference the cleaning made.
Are you capable of, and willing to do the cleaning yourself?
Can you afford to pay someone that you can trust for this service?
Do you have a tech friend that can help you do this so you can learn?
I can't answer these questions for you - they are your decisions.
IMHO every PC including laptops need periodic cleaning maintenance.
If you want to clean fans in a laptop, you or someone has to open it up to be able to clean the fan(s) correctly.
I've never seen a laptop with fan(s) and heatsink(s) that can be accessed and cleaned without opening it up.
I use, build, and maintain desktops, so cleaning is much simpler.
I can easily pull off a side panel to see, access, and clean the fans, heatsinks, etc.
You could just buy a can of compressed air and blow out the dust from the vents and all openings.
But, where does that dust and dirt go?
Common sense tells me - right back into the laptop if it is not opened up!
Wonderful - now more dirt spread around inside the laptop!

This approach may help short term, but what about long term?
Maybe you don't care about long term, i don't know.
Maybe I'm wrong
You could use a vacuum to pull dust and dirt out before using compressed air for cleaning.
But, many say a vacuum can cause a static discharge damaging electronic components.
Personally i would first vacuum to pull dust out of the laptop, knowing the 'static danger' and following recommended precautions.
If that didn't help enough i would then use compressed air ...
This is my opinion based on my experience...
NO GUARANTEE here
This also assumes you can't or don't want to open up the laptop for cleaning...
So, how capable, competent, and willing to learn are you with hardware, specifically a laptop?
You could search for cleaning instructions for YOUR laptop and maybe find an online (Youtube) video.
Are you willing to do that, and carefully follow the instructions?
Also:
Whenever i add new memory, move existing memory, or reconfigure memory...i run a memory test.
Better safe than sorry - the choice is yours.
hope this helps,
David