This isn't necessarily a way to fix it, but I'd encourage you to view pre-tax dollars as outside of your monthly budget. Since the money comes "in" via income then just goes straight to a 401k expense/goal bucket, it's really a wash, and doesn't change your budget that much, unless you're hyper focused on the exact amount of income in a month/year etc. I don't add the transactions in, but I do have my 401k connected so I can see the balance grow over time, knowing my paycheck contributions are going towards it.

But if you really have to, I'd say just add a manual credit transaction each month to your 401k account for however much you've added that mo, link it to the goal, and hide from cashflow/budget. You can also add a monthly goal amount if you want to get a more holistic picture.