I totally get where you're coming from. It can be really challenging to navigate these issues, especially when you're trying to target a specific audience and end up dealing with unwanted comments and potential fraud. It seems like the algorithms of these platforms still need a lot of work to provide more precise targeting and filtering options.
You are already collaborating with influencers or partnering with brands that have a strong following in Tier 1 countries might help you reach your desired audience more effectively but as you said you are facing the same problem with this approach too. Sometimes leveraging the networks of others can provide a more focused and engaged audience but hard luck here as well.
Have you considered exploring other marketing strategies or platforms that might offer better targeting for your needs? For example, some businesses find success with email marketing campaigns, where you can have more control over your audience. You could also look into platforms that cater specifically to your target demographic or industry, using this option your posts will not go Viral though.