Enerwave ZWN-RSM1-PLUS Relay connection issues

I’ve been attempting to get a pair of Enerwave ZWMN-RSM1-PLUS relays to stay connected to my hub with little luck. I’m using the relays to control a pair of light posts in the front yard (desitance between the hub and the two post lights is roughly 120 and 150 feet). The relays would connect but only for a couple of minutes (I believe the longest one of the relays stayed connected was around 30 minutes. I even attempted drilling a small hole through the post and threaded the antenna out of the metal post. Still no luck.

I figured I was right at the edge of the Zwave range (considering the signal had to pass through at least 1 wall). Based on that I purchased a pair of Enbrighten Z-Wave Plus LED bulbs and placed them in exterior fixtures on the outside of my garage which reduced the distance to the nearest post to roughly 85’ with a direct line of site between the fixture and the post. At this point I was able to get the relays to connect and stay connected between 12 to 18 hours but they still eventually drop.

The last couple of days the posts would drop off and the Enbrighten bulb physically located farthest away from the hub would drop off at roughly the same time. I’ve shifted my hub (which also moved it away from my wireless router by approximately 15’) to a location that puts both the Enbrighten bulbs roughly the same distance from the hub (litterally within 2 or 3 feet and with the same number of walls between the hub and the bulbs). At this point the Posts don’t want to connect at all but both bulbs are connected.

Could 1 of the bulbs be corrupting the mesh network table somehow? I think I’ll try disconnecting the bulbs 1 at a time and let the network sit for a bit and see if anything changes.

Any ideas on what I could try if that doesn’t help? I’m willing to try a different brand of bulb or relay but I’m fairly new to the home automation scene so not sure which brand to shift too. There literally isn’t anything between the light bulbs and the posts other than the fixture glass and air. At 85’ I wouldn’t expect a week signal to be the issue (however I’m not able to confirm that since we still don’t have any kind of network map with V2 Smartthings hub).

Oh, and why the relays in the posts vs a zwave switch? I have some additional lights located out next to the road itself that I want to stay on overnight so I control them with a light sensor but don’t want to leave the post lights on all night. Everything is controlled with a single switch.