I'm sure everyone has seen the profanity-laced comments that have been made on video by Prigozhin in which he has very harsh criticism of the defence minister, the chief of the Russian defence staff, etc. I think you can conclude from those comments that there is not unity within the Russian presence in Ukraine.
There is, at minimum, rivalry between some elements of the Russian military and Prigozhin and his private forces present in the country. Whether this has any impact on President Putin's stability and hold on power, it is very difficult to say. As I mentioned in my opening remarks, Putin does have a history of tolerating rivalries within his inner circle, for reasons I think we can speculate on, but perhaps it's best not to.