It’s not a conflict, it’s a feature.
When you add edit restrictions, they are applied to all post types by default. Thus, user can see just those 2 pages and do not see any ‘mytestimonial’ items. If user should see all ‘mytestimonial’ posts, then you can exclude ‘mytestimonial’ post type from edit restrictions scope. Use this hook for that – replace ‘post’ in a code sample with ‘mytestimonial’.