I tried the Orico BTA-403 dongle and that definitely does not work. I have tried various other no-name dongles that do not work. I also have some of the Laird 820 which work fine and which I use to allow the TextBlade to be used on systems without the requisite Bluetooth support.
The dongles we have used successfully are all based on the same basic chipset, but a key factor seems to be whether the dongle has 32K or 64K flash memory internally. All those that we have managed to get working have 64K while the ones that have failed only have 32K. Unfortunately the manufacturers do not include this level of information and are not amenable to answering this type of query. I was hoping that at some point WayTools would host a Wiki and then we could add details of ones that are known to work to help guide others as to which ones to use and the steps necessary to get them into acting as a HID device. The process that the TREG group has used for getting dongles working seems to work reasonably reliably if one has one of the known working models.
The fact that it is possible to get dongles that work makes me suspect that it is highly likely that Waytools is investigating providing dongles as a standard accessory. However until they announce something in this space that will be all supposition.