"Can you just take a look at it" (for free) answer - no way.
For my qualifications and licences I spent five years as a Telecommunications Technician then fourty years at night school covering all aspects of electronics.
I once run a TV repair shop were all sorts of things came in with no circuit available and fixed them day in day out by the truck loads.Yes, I know the secrets to fixing things without a circuit.
I worked in Asia designing software and hardware for mass production items which many of you have used.
I have done everything, yes everything in between.
I am currently in maintenance, repair, calibration and certification of heavy aircraft avionics systems, and I am an Engineer.
Don't tell me Engineers know nothing its a totally dumb generalization.
How do you know what they have done before and if they have a solid back ground in other areas.
You know how it goes - My mechanic will not service my car for free so I don't expect others to ask me to fix things for free.
I am very familiar with RC systems.
I have done work for manufacturers, I used to go around to agents and importers and tell them I would fix items returned form stores for a fixed price per item. Its called "piece work", its rugged work.
Among those customers were some RC importers.
Its not what you do, it needs the expertise and some basic equipment especially since it may involve RF, the equipment is not cheap.
In electronics we call RF the black art because to other technicians that are not familiar with it it seems like a black art.
Throw them away and buy some more its cheaper than paying some one who can do it.
If you did find such people on forums, you couldn't do what they ask or communicate with them anyway.
For example at the start I found I couldn't fix things because I couldn't even solder to a good enough level to fix things.
The guy who finally taught me to solder started out by saying "Its going to be hard to teach you how to solder because you already think you can".
Same goes for fixing things, you already think you can.