If this is the case, if I ran this process ot 64-bit would it solve this?
No, we have processed many heap dumps from 64bit machines and we have seen
ridiculous big objects - running MAT on 64bit will not change anything.
Keep in mind that the VM itself does a garbage collection before writing
the heap dump. So the heap dumps are usually slightly smaller - but, of
course, I understand you are talking about much bigger sizes. Sorry.