Looks like there are some fact issues (i.e., "Consent") that would preclude the grant of such a motion. The article states: "Bowers [the plaintiff's attorney] would not say how Jones forced Weckerly to submit to the alleged assault." That said, I have no idea what theory should could possibly use against a 71 year old man.
Under the statute, there are a variety of theories available:
§ 22.011. SEXUAL ASSAULT. (a) A person commits an
offense if the person:
(1) intentionally or knowingly:
(A) causes the penetration of the anus or sexual
organ of another person by any means, without that person's
consent;
(B) causes the penetration of the mouth of
another person by the sexual organ of the actor, without that
person's consent; or
(C) causes the sexual organ of another person,
without that person's consent, to contact or penetrate the mouth,
anus, or sexual organ of another person, including the actor; or
...............................
(b) A sexual assault under Subsection (a)(1) is without the
consent of the other person if:
(1) the actor compels the other person to submit or
participate by the use of physical force or violence;
(2) the actor compels the other person to submit or
participate by threatening to use force or violence against the
other person, and the other person believes that the actor has the
present ability to execute the threat;
(3) the other person has not consented and the actor
knows the other person is unconscious or physically unable to
resist;
(4) the actor knows that as a result of mental disease
or defect the other person is at the time of the sexual assault
incapable either of appraising the nature of the act or of resisting
it;
(5) the other person has not consented and the actor
knows the other person is unaware that the sexual assault is
occurring;
(6) the actor has intentionally impaired the other
person's power to appraise or control the other person's conduct by
administering any substance without the other person's knowledge;
(7) the actor compels the other person to submit or
participate by threatening to use force or violence against any
person, and the other person believes that the actor has the ability
to execute the threat;
(8) the actor is a public servant who coerces the other
person to submit or participate;
(9) the actor is a mental health services provider or a
health care services provider who causes the other person, who is a
patient or former patient of the actor, to submit or participate by
exploiting the other person's emotional dependency on the actor;
(10) the actor is a clergyman who causes the other
person to submit or participate by exploiting the other person's
emotional dependency on the clergyman in the clergyman's
professional character as spiritual adviser; or
(11) the actor is an employee of a facility where the
other person is a resident, unless the employee and resident are
formally or informally married to each other under Chapter 2,
Family Code.