Nope, that definitely isn’t safe, I’m afraid.
Just because you haven’t heard of any problems doesn’t mean it’s safe. You’ve no idea what the host will do when you invoke that call, but it’s very likely that some of them will allocate memory or post a message, which will occasionally cause problems depending on what else the host is doing at a particular moment.
The only safe way to send events from your process method is to have your own lock-free fifo to post events which you later pick up in another thread (or on a timer) and do the work there.