Wasabi is basically horseradish.
Chilis are peppers.
If you really want to sub something halfway resembling chili sauce, a better replacement would be the commonly available Tabasco or Sriracha type sauces.
Thanks for your answer CV...you are correct of course, but sadly, I did not have your suggested chili sauce substitutions...(so, I thought, "3 strikes...I'm out"!) But, I carefully mixed in the horseradish sauce, tasting samples along the way...(this was to be a beef and spanish rice casserole)...and the nearest store is 30-45 minutes away...and I had all but the chili sauce in the pot simmering! Well, the finished dish got rave reviews, and as you can see in the attached photo...several servings have been consumed! So, I got lucky...need to restock my pantry pronto.
Well, if your diners enjoyed it, that's really the final word.
For sure, the resultant dish was considerably different than what the recipe author intended, so you should feel satisfied that you have modified it to the extent of creating something new.
Wisely, you tasted as you went along so you did not blindly blunder into this.
So you got lucky on this dish, these sort of substitutions don't always work but luckily your diners benefitted from this good fortune.
Indeed a chili sauce would have been the more appropriate call for a beef and Spanish rice casserole, but a beef and wasabi rice casserole clearly satisfied your dinner guests. But they are different dishes with different flavor profiles.
Congratulations for contributing to the ever-expanding Asian fusion repository of recipes.
Thanks CV...you are right again...I got lucky...the flavor profiles of the two are very far apart simply because of the flavor prominence of the original and my wasabi substitution. And the kicker for the evening was when one of my guests asked for the recipe! I have named it appropriately - "Ground beef and wasabi rice casserole" for the quest.