I'll just say this: if there were no reason for the special tools and procedures to exist, then why would VW/Audi/Volvo have gone to the trouble of creating them? Manufacturers want to make routine service procedures as simple as they can, because car owners dislike high maintenance costs. ALL older, non-computerized diesel engines (not just the D24) call for complex timing methods requiring special precision equipment because it's the only guaranteed way to preserve the performance, emissions, and reliability the engine is intended to provide. Other methods might SOMETIMES get close enough due to sheer blind luck, but almost always they will result in an engine that runs poorly, doesn't run at all, or sooner or later self-destructs. Luck is nice, but you sure don't want to rely on it.
No offense to your friend, and no doubt he had the best of honest intentions in trying to help with his idea, but I don't think you will find anybody here agreeing that you should ever attempt to cut corners when working with the timing belts. The proper procedure and required tools are the only option.
But fortunately the truth is that if you have the right information and tools, doing the timing belt job the right way is not difficult at all. You will need to allow plenty of time to take with it, but it's not rocket science and nothing to be afraid of. The thing you SHOULD be afraid of is trying an "alternative" method that doesn't end up working out.
Welcome to the forum! There are several members here in France, a number of which have the correct special tools and some experience with the timing belt procedure. One of them might be able to comment on ways to get the tools where you are. And the rest of us here are happy to help with information on any tasks you may need to do.