I run a legaltech in the UK. Other than dealing with a similar case with my own co-founder (I ended up splitting ways very early which in hindsight I'm glad I did), we've dealt with a case on the platform where one co-founder wanted to oust the other for similar reasons. Not even thinking of this with a legal lens, if trust is already an issue, you need to have a 'hard conversation' with him. Trust is everything at an early stage, more than the problem.