Yea, there's a lot of risk here since you're helping your children and they're priority. Are there any other options you two have other than marriage so your finances aren't intertwined which would still be satisfactory for the both of you relationship wise?
From what we know here, I would still stay in the relationship, but stay away from marriage until there is enough financial stability coming from his side. There's this feeling of urgency coming from your post that is overwhelming and it may be good to think about where that feeling of urgency is coming from. Is the feeling of urgency being induced by your boyfriend because of his situation? Is there something in you that is reacting to this situation that is igniting the urgency? The urgency of the marriage is an issue. Hope this was helpful.
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