I am not aware of any method outside of Compiler that will allow you to do that.
The only 'alternative' I know is using GNU Octave. This will probably require a lot of work to make it compatible (Octave calls itself 'mostly compatible' with Matlab). There are a lot of downsides to using Octave, but one of the upsides is that it is open and therefore a lot easier to package your GUI with a portable runtime.
You would have made the refactoring task a lot easier by not using GUIDE (see this discussion).
Be aware that there are several downsides to using Octave: it is slow, has missing functionality, is poorly implemented on Windows, and has a much smaller community (and no official support you could contact). But it is free in most cases, so for some situations it may be a good alternative.
Note that since this is a Matlab forum, provided by the company that sells Matlab, discussion of Octave is generally discouraged (although not explicitly forbidden). When posting questions, try to make sure the issue can be reproduced in a release of Matlab (older releases tend to share limitations).