The thermocycler replacement using an electric kettle is hilarious. Thats how old school dna amplification would happen before the invention of thermocyclers.
OP you'd get better results of you centrifuge your blood, extract the white blood cells and sequence those instead of whole blood. Thats a bit tricky with a lance and a tiny device though...
When I was in school in the early 2010s (maybe 17-18yo) our intro to biology course had us thermocycle by alternating between warm tubs of water with the use of an egg-timer. When I later used a thermocycler during my research career I really came to appreciate the little bugger (even though it caused a lot of headaches anyway)
Now you can buy a portable thermocycler with 13k rpm centrifuge all-in-one with gel electrophoresis - BentoLab for £1299 in UK. Carry case £54. (They sell a Dipstick DNA Extraction kit for £38.50, pipettes, and mastermix...)
OP you'd get better results of you centrifuge your blood, extract the white blood cells and sequence those instead of whole blood. Thats a bit tricky with a lance and a tiny device though...