First, I agree with the uTube stuff. Anything there must be viewed as "user beware."
But I am a believer in that someone is always developing "a better mouse trap." So I checked out this Trojan Killer that the uTube video is about.
First, I never heard of the software. There isn't a lot of info on it on the web. The few comments that exist seem to indicate that the software does work. Now for the "meat and potatoes." The company in in the Ukraine. That is red flag number one. Next the full version of the software costs $40 - you got to be kidding? The trial version is a limited version. Good for 15 days. It is limited to 5 malware removals - red flag number 2. "Premium" tech support is currently on sale for $10 - red flag number 3.
You have to use some common sense. If a vendor offers a limited trial of their software and the trial has use restrictions, look elsewhere. If the vendor has not been reviewed by reliable and knowledgable sources, look else where.
I agree that the first place you look for help is from your existing anti-malware software/s vendor/s. If they can't help. then go to the established anti-malware removal sites like BleepingComputer. Or if your not technically inclined and have the financial resources, your local certifed computer repair shop.