Reverse sneezing with Multiple other symptoms

Hello, my pup has been what closely resembles reverse sneezing for about 2 months now. It has gotten progressively worse and now occurs multiple times a day for various durations. I’ve been to multiple vets with no answers… I have scheduled an appointment with an internal medicine specialist for mid next week but I thought I would try to get some input from the internet so I can go in with as many questions as possible.
She is completely up to date on shots. Has her heart worm prevention monthly. they pulled blood work, they called it an elderly dog wellness check or something? Either way they said the tests look good/normal

Heres some other symptoms:
-Swollen lymph nodes/ bump on right side neck under jaw.they tested for cancer but they stated “we weren’t able to find anything cancerous but we cant be sure”
-recently it seems she is having discomfort moving her jaw. Grabbing treats,barking and eating makes her jerk her head to the side in pain
-there is very occasionally discharge/snot when she sneezes
-very lethargic. She’s 9 y/o but is usually pretty active. Shes been sleeping day in and day out for the last month or so
-her appetite has taken a toll but it is definitely still there.
-if I think of or notice more I will add

She has had 2 ACL surgery’s(both back legs) in the last 3 years witch are still being paid off and with all these new vet appointments,money is quickly becoming an issue on getting her help…

Any other information that’s requested I will add as soon as I can. I have a video of the “fit” if needed

I have had her since she was 8 weeks old and she is more than important to me. Absolutely any input,advice or guidance would be more than appreciated.