Let me ask you this: does the Church approve of what you propose to do?
The fact that people feel at liberty to do what they wish despite what the Church has said for us to do, is certainly sinful, and any sin (even one that is deliberately venial) can only be a step towards hell.
That is a good question, one I should ask my priest about.
The problem is that displinary measures are not the same as dogmatic teachings. If the Pope you quoted was still alive, I wouldn't dare disobey him.
But, I don't even know if those instructions still apply today. I don't have the slightest idea of which disciplinary rules must still be obeyed in 2026, and which can be considered to be "obsolete".
Those rules were made where most of society was Catholic, and when there was indeed a high risk of causing a scandal if one were to publicly pray for the sake of a known unrepentant heretic. Moreover, the Popes who made those rules were concerned about the risk to their flock of faithful. They made those rules, in order to be sure that at the very least, those rules wouldn't be harmful for salvation, for potentially millions of people following those rules.
I dare say that, at the very least, if you obey the Popes on this matter you will not be led astray.
I think that, for some personal reasons I would rather not discuss here, in my particular case I have a legitimate gray area where it's unsure if I should obey those instructions or not.