I am confused. You say you Reverse Integrate(RI) all hotfixes back to Patch. So Patch accumulates every hotfix. But you say you cannot get previous hotfixes in subsequent ones. If you are doing RI from each Hotfix back to Patch and Dev, then when you make a branch from Patch for a future hotfix, it should have all previous hot fixes. Are you doing RI for every hotfix or not? Is your branch design a proposed theoretical one or one you have been actually using it for some time?
Also, I am not clear on your hotfix approach. Are you sending the customer an entire package of the product with a special fix embedded in it? Or a piece of add-on code that will modify a base installation. Those are drastically different approaches and the final result of all this depends on the answer to both of these questions: whether you RI hot fixes, and how you deploy them.
If you reveal a little about your underlying technology platform (like WIndows Forms vs ASP.Net web forms, etc...) it may help.
