@MarqFJA87 We can safely assume that Risu knows Fulio's powers to some extent (they are husband and wife, there's bound to be some communication on the topic off-scene), but only to some extent because even Fulio himself doesn't know how powerful he is. This is supported by the fact that in the earlier chapters it is shown that he has an infinite amount of pretty much everything in terms of stats, but he doesn't know what the infinity symbol (∞) means. He also isn't actively gauging his capabilities as often as some heroes do because he used to be a merchant that just suddenly became very powerful, ergo he's more used to trading with money than trading with blows to the enemy.
Tl;dr: I agree with your point and just made your reasoning more solid.