You got a couple, MAYBE options.
1. March 27th is a long time away, we don't know what the future holds.
2. >My original plan was to apply for a 60 day tourist visa in Vientiane but this appears to be off the table for the foreseeable future.
*MAYBE* it'll work (but I don't think so). You will need to get a visa to enter Laos. According to:
*******************************************************************************************************
"Issue visas for visitors who intended to visit the Lao PDR with non tourist purposes only. Visitors will have to submit requisite information on their health and related documents to the Lao diplomatic missions *in the country they are resident* for approval before the intended date of travel."
I do not know what the bolded part means. We have one report of someone trying to get that visa to Laos to get a Thai visa, and it was denied by the Laos consulate.
>What options are available to me to insure I remain legal during the interim period between current visa expiration and work permit issuance.
You *MAY BE* able to get a visa to enter Myanmar and fly in. You can then take a bus back into Thailand. It'll give you a 30 day visa exempt, with the option to extend it by another 30 days.
That's the only two options I can think of.