I don't see why not. The Luca app handles the certificate of vaccination just like the other two: you scan the QR code from your vaccination certificate in, then you can show it at restaurants, museums, etc. I have my (German) certificates scanned into Luca and also into the French "TousAntiCovid" App because the German Corona Warn app doesn't run on my Smartphone. (

) I often use the French App in Germany to show my certificate because it is easier to use than Luca...
I cannot speak for the Allianz Arena - is there a FlyerTalker from München here? - but I don't know why they should refuse to look at a valid certificate just because it is stored in Luca...