Welcome Back

Nice to hear from you!!

Let's first look at the II Mach. 12:46 verse. To be sure, this is not common ground between Prod and Cath (nor between first century followers of Judaism and modern Catholics, as this was not considered a part of the TANAK, or Hebrew Scriptures), however let's look at it anyway.
I would suggest the the reference itself (as is often the case with Scripture Prods would hold dear) is that it does not say that what Judas M did was right, it simply records what he did. He was concerned for his dead soldiers who were found with foreign gods under their cloaks. Fearing that they would not be accepted by God in the afterlife, he collected money for an expiatory sacrifice to be made in Jerusalem (vs 43). He then prayed for the atonement of the dead. Although the text describes Judas as being noble and pious in his thoughts, it does not necessarily mean his actions were correct. He could very well have been misguided.

As for your Matthew 5:7, argument, I do not think that is the reference you meant.