The War Department cleared the use of proximity fuses for land artillery in 1944 and Eisenhower requested their use during the Battle of the Bulge. By 1945, I'm sure army air defense units also were given proximity fuses shells so there is a good chance that the 90mm guns used them at Remagen.
I know, and they devastated German infantry so bad they caused desertions. What I find odd is I cant find anything out about them being at Remagen.
Yes one can assume they were there but there are a few things to keep in mind. #1 is that the plan was always to construct bridges and two were underway during these Remagen attacks. #2, Is that the Ardennes isnt Germany and even if it was just psychological there might have been caution towards shooting them into Germany especially with so much hard fighting still to be done. Nobody knew how much more fighting.
#3, Too; Is it possible the shells used in the Ardennes had dual fuzes, both proximity and contact, which lowered the chances of the Germans getting ahold of an intact one? This was one of the biggest secrets of WW2 after all. And dont forget the COC of the entire Theater had to scream like hell to get them released in the Ardennes so obviously this had to be a decision he had to get Pentagon approval for.
When you add it all up you cant help but think it is possible they weren't in those AA shells.