Advice Needed! P0401, P0300, P0301, P0303 Head Gasket and/or EGR?

I wanted to check the magnet on the EGR valve currently installed in the car which I believe is the original one. Went with the family to get some bobba drinks and to my surprise the CEL had come off.
The car was in use until now and so the engine is still too hot and I’m too tired to take the magnet off, hopefully I can take the magnet out and compare it to the one for the replacement valve in the pictures. Actually, even better if the CEL doesn’t come on again at all ☺️

 

Interesting question, what do you think @ChapmanF?

If the cooler in my car is squeaky clean (at least for the time being) I would imagine it will cool better preventing the valve from getting as hot as a dirty cooler would.
The question is, how long will it take for the cooler to start getting “dirty” letting the valve temperature increase?
Probably have to use the most heat resistant material that I can find to fix the ski slope (ramp) on the magnet…

 

It is too bad! I found one online for $150.16 (USD) + shipping so here it will be less than $200.00, still a lot of money for a little tiny piece of worn-out

 

Alright, went to take the magnet out of the car’s EGR valve, didn’t do it last night because the car was too hot. The car has been parked for 4-5 hours so I thought it would be nice and cold. I didn’t count on my better half leaving the car on all this time!
Anyways, I carefully took the magnet out and was happy to see a very (very!) clean magnet and plastic ramp (ski jump)! I’m now more confident on the P0401 error actually coming from the replacement EGR valve due to a damaged/worn ramp.
I’m planning to take a short road trip with the family in the Prius, wish me luck, will report back asap. Thank you again for all the help!

 

I didn't know that, I will make sure to tell my wife, hopefully we can avoid it in the future, thank you for all your help @rjparker

 

Well this weekend I tested the head gasket. Took the family up north (2 hours drive each way), 80mph uphill gave the motor a good workout. Happy to report no loss of fluids, no warning lights, no overheating, no issues at all. If I don’t get a good deal on a car very soon (or if I decide to get a car with a bigger engine and keep this one) I will procure a new break booster assembly (I know is better to replace the accumulator at the same time but…) and replace that. After the breaks I would like to save for a new traction (hybrid) battery but who knows…
Thank you again everyone for your help!