Never use a partner/vendor to manage your selection
Use an independent consultant or selection firm to manage your selection.
It goes without saying that using an ERP partner/vendor to 'assist' you with your selection is an obvious no-no. They are hardly likely to recommend an alternative solution to theirs unless it is very clear that your solution is genuinely 'out of frame'.
You must also be careful when hiring selection consultants or selection partner firms to ensure that they are truly independent i.e. free of any commercial ties with any partner/vendor involved in your selection process.
Otherwise the selection will inevitably be subject to the commercial 'lens' of your selection consultant/partner who will tend to view everything through this lens whether they claim to be independent or not.
Lesson: Hire a truly independent selection consultant/partner for your selection.