Can freezer jam not be frozen if sealed?
Only recipes from trusted sources should be used for shelf stable canning, as they are proven to produce a product with a sufficiently low pH to be safe when stored at room temperature.
The boiling water bath process is a way to create a vacuum seal, it is also a way to get the contents of the jar to near boiling for a certain amount of time, this will kill most microorganisms (any remaining will not be able to thrive in the low pH high sugar environment).
As you are not using a recipe specifically designed for a shelf stable product and you are not putting very hot jam/jelly into the jars prior to processing (you have no way of knowing how hot the center of the jam gets), your jam will not be shelf stable.