How about deleting the thread locking agent and doing without? You don't need it for sure.
If you feel like checking and a retorque after a few drives, that gives you an excuse to have another session in the garage
I'm guessing you are in calibration then. I once had an interview for one of the worlds largest fastener manufacturers in which the technical director , whom looked exactly like Yul Brynner suddenly and dramatically placed both hands on the table, gave me a mad stare and and actually whispered "Define torque".
I still remember my answer 20 years later was "torque is a twisting force applied about a central axis and can be said to cause rotation of an entity" I got the job and to this day I travel the land explaining (amongst other things) the effects of lubrication on torque figures that were calculated for dry assembly. clamp-load increases dramatically for the same torque figure where a lubrication is used. The better the lubrication, the higher the clamp load for the same torque and the higher the chance of failure. A locking agent will lubricate any threaded assembly to which it is applied....
Anyway, enough of this torque
Having re-read this whole thread properly I must now confess to not reading your original post properly and I thought we were all talking about the actual head studs. Apologies for this. Given the duty of the application and the fact the originals are designed with the spring washer and the joint designed to be torqued to a given figure to take their presence into account then I refer back to my poor quality components theory which was where I started. This seems to be very likely given the spring washers are disappearing in bits up inside the nuts.
I would certainly remove the lot and get better quality components as you don't want bits in your oil. I can have the bolts tensile tested for you if you want to have some data to supply your supplier. I really dislike any new components, they are never of OEM quality and I'd reuse bolts every time before buying something that cannot be checked for serviceability prior to fitting.