Why would you get an 88 and a 92? It's pretty clearly just the Legend Tier rewards + a 94 UL card. Other HR rewards aren't going to apply here.
That would be sick if we got all of them. But I bet it's just the 94. I kinda wish it was a 94+ vs. just having the other cards too. Low odds of a full UL, but at least the possibility would be there.
Usually rewards are added up like you are suggesting. This does not seem to be the case with HR solo battles, sadly.
I think it's only one card. If you hit 300 you get the 94, between 210 and 299 it's a 92 etc.
Does this mean we get an 88 an 92 and a 94??