3 Months may not be so unreasonable depending on the unit and the mbr. Some units have 3 locations. If mbr is at location 3, waits until last minute (or even after his releases date) to clear the unit and sign off everything that is a delay. The CO is at location one so the paperwork has to go in the mail to that location, be vetted and put in for CO signature further delay. CO is away for a week or two and you have another delay. Once all signed a final verification has to be done, hope there is no error, then file sent up the chain. 3 Months could be the normal mark for some locations.
The ROE is issued electronically but is not a totally simple form. That said the issue of not having anyone qualified in the unit is a really lame excuse. The C Clk should be contacting bde and requesting assistance in the form of someone going to the bde for a day to learn it (at unit cost as it is a unit issue).
Going higher than the clerk is good advice but you should start at the unit CofC level instead of going direct to bde. RSMs/COs need to be made aware from the mbrs and given a chance to deal with issues rather bombed from above.