That’s a very clever argument you have devised however it’s ultimately self-defeating.
I’m quite certain you believe Jesus’ shed blood is the atonement for your sins. However His Blood was shed on a cross not splashed on an altar.
So if the only way a blood atonement can be effectual is if it is splashed upon an altar and no other way, then Christ’s Sacrifice is of no effect. Which is ludicrous of course but that’s the natural result of your logic.
Thus, since there is no reason to believe the shedding of blood must be splashed on an altar in order for it to be effectual for the forgiveness of sins, then it cant be argued, as you have, that since we Catholics aren’t partaking of the Sacrifice, the way God commanded (in the OT), then it can’t be of any effect.
You aren’t either, that’s the point. The fact that you don’t drink His Blood is of little relevance to the original argument you are making. You still ultimately believe in a method of atonement that is itself, not exactly like the command in Lev 17:11, which is the same criticism you are attempting to level against Catholicism.
So if you’re correct in your rigid interpretation of Lev 17, then you have no means of salvation through His shed blood either, blood shed not on or splashed on an altar but on a cross. A cross is not an altar.