I'll ask around but I believe the answer is no. The property isn't exposed in Redfish as far as I know. It's exposed via racadm with getslotname
.
$ getslotname
<Slot #> <Slot Name> <Host Name> <iDRAC DNS Name>
1 SLOT-01 fx-idrac-640
2 MINWINPC MINWINPC fxi2blade2-idrac
3 SLOT-03
4 SLOT-04
When you see this page on the iDRAC:

under the hood it is calling the following function:
function getBladeSlot(xmlDoc)
{
var xmlNode = getXMLValue(xmlDoc, "deviceLocInfo");
if (xmlNode != null && typeof xmlNode == "object") {
xmlVal = getXMLValue( xmlNode, "devBladeSlot" );
if (xmlVal == null) xmlVal = "";
idracBladeSlotNum = xmlVal;
idracBladeSlotName = " " + top.localeObj["gen_slot"];
idracBladeSlotName += (idracBladeSlotNum < 10) ? "-0" : "-";
idracBladeSlotName += idracBladeSlotNum;
}
}
which is referencing the iDRAC's internal data schema. None of this is Redfish stuff. If you wanted to go to the trouble you could definitely replicate that functionality programmatically with something like Python, but it seems much more straightforward to me to just call racadm from Python or something.
I do a lot of Redfish dev and I couldn't find anything anywhere that indicated to me that this is exposed via Redfish.