suspicious to ALS

Hello:
My father is 59 years old. About 7 months ago his lower lip started twitching occasionally. It twitches more when he bends His neck to the right. About 1 month ago or a little more he started having nasal speaking. Sometimes he speaks like he is drunk. The MRI from the brain was normal. Level of lead (Pb) and cadmium (Cd) were normal.
Cervical Spine MRI showed small central protrusion between c3-c4 and tiny central extrusion between c4-c5,
Disk dehydratin:c5-c6 with decreased disk space and partial dehydration at other levels.
C5-c6: diffuse bulging and posterolateral spur-disk complex with moderate canal stenosis.
Bones and bone narrow: mild degenerative spondylosis
Cervical spine curve:reversed lordosis of upper cervical spine and mild scoliosis with convexity to the right side.
The X-ray form his chest was normal.
EMG/NCV results:
1-normal CMAP amplitude of all tested nerves and some slow NCV that maybe due to hand coolness.
2-No FIB/PSW in tested muscles, but significant slow fasciculation  potential in tongue, and triceps muscles.
His nasal speaking comes and goes, most of the time after eating it becomes worse. When it goes it’s not normal but the difference is noticeable.
Some days it’s better than the others.
His tongue is weak. Other parts of his body are still powerful, sometimes his arm twitches too but there is no weakness in it.
He is using these drugs:
Gabapentin 300mg(3 times a day)
Zoloft  50mg
Atorvastatin 40mg
Selegiline Hcl 5mg
B-complex
Vitamin E
The blood test:
SGOT, SGPT, alkaline phosphatase, Ca, inorganic phosphate, Total protein , IGG,IGA,IGM,IGE, serum protein electophresis,thyroid
were normal.
Anti HTLV1-2(ELISA) is 0.1(negative)
Stool test:
Occult blood was negative………………
May it be ALS bulbar onset? How much would it progress in a month? Does it come and go (sometimes better than other times?)
Can stress cause nasal speaking and tongue weakness?