Subaru death

hey i have an 01 sub outback wagon which just started getting a check engine light - v long story short.
headgasket resurfaced -20k miles ago 90-100k then, now at 127k, had to get new tires and alignment and oil change
and NO SOONER did i pick up car from recommended tire shop, did it start smelling funny. like…oil? rubber? not sweet like coolant.

called tire shop asking how long will i smell this from new tires (they say slight coating should wear off); 1000 miles later, some intermittent yet strong smells (from tires? or engine? not sure never got to determine pattern (hills? turns? highway etc), check engine solid.

ok not going to drive it, left mesg for mechanic. next morning, check engine blinking, a mile away from / slowly enroute to garage. when my mechanic looked into it, diagnostic for 3rd cyl misfire. somehow during a test drive or reparking car a part came off (red hot, ball bearings?) and car stalled; took a day to reassemble. no charges yet. also green rad fluid was leaking down before they diagnosed CEL.

question, did they tire shop somehow sabotage my car? no issues, no redlining, etc since HG work 2 yrs ago, but oddly enough my car is on its deathbed now and my mechanic wont work on it, bc he is not sure if internal issue and other paying jobs more straightforward. and he recommended the tire shope to me and in my frustration i asked him never to recommend them to anyone ever as my car was fine UNTIL they had access to it (tires align oil chng). coincidence? i had to wait a few months to get the tires bc AWD thus 4/time, i am a poor adult student.

so my mechanic tried HG seal, radiator just has water in it, and while no CEL light, it feels like it’s going to overheat, not smooth at stopsigns, only driving to park to avoid streetcleaning tkts…help. i owe 1k on the car and afraid if i try to sell at dealer it will be 800$ if lucky. my mech wont work on it prob bc expensive time and money sink and i got impatient stopping by (after waiting 4 days for his vacation and him saying come by monday and i will call you monday and at 330 on monday stopping by, a busy customer day so he returned my key saying good luck, get a 2nd opinion, i’ve lost a week waiting on this problem by him not communicating with me - he could have said that last week!). i am so broke i qualify for a pell grant and wondering if worthwhile to sink 2000 for new engine or how much they cost instead of buying someone elses lemon. donate care fix car 'why is my car all of a sudden on its deathbed?! oh yes and need star smog in sept if that makes matters worse. what would you do? mechanic’s special sell “as is?”, repair? then sell? trade in?

I had to read this three times to understand what you’re saying.
So the car now has no CEL light but is leaking coolant? Is it leaking from the heads again?